<p>To fully answer the question, I'm gonna go back to the Third Great Ninja War, where Obito was a kid.</p>
<p>The Village Hidden in the Leaves is currently at war with the Stone Village, and Team Minato is on the battlefield. Obito and Kakashi are facing a Stone Ninja with camouflage abilities. He uses them and slashes Kakashi's eyes in the process. This leaves Obito crying and awakens his Sharingan. When the invisible Stone Ninja is coming up, Obito uses his Sharingan to track him down, then finishes him with a kunai.</p>
<p><strong>This is how Obito awakened his Base Sharingan. (2 tomoe)</strong></p>
<p>The squad of Stone Ninjas have captured Rin Nohara, Obito and Kakashi's third squadmate. After finishing the Stone Ninja, they go to rescue her. They fight with the Stone Ninja, and after, he leaves the area and uses a jutsu to make the cave they fought in collapse. When Rin, Kakashi, and Obito are running away to exit, Kakashi gets hit by a falling rock and falls. Obito then goes back to save him, and gets crushed by a falling boulder. His right side is nearly completely crushed. He gives Kakashi his left eye's Sharingan as a gift for becoming jonin. The remaining members then run for the exit.</p>
<p>By chance, the place Obito was crushed was near an underground passageway that Madara Uchiha created, and Madara then took and healed Obito to use him as his pawn to revive him. While Madara attends to Obito, he injects almost his entire right side with Hashirama Senju's cells, and White Zetsu also attaches himself to Obito's right side.</p>
<p>One of White Zetsu's clones alerts Obito that Rin and Kakashi are in danger and surrounded by Rain Ninja that seemed to be Jonin or Black Ops. Obito then destroys the exit to Madara's lair and runs to aid Rin and Kakashi. By the time he gets there, he sees that Kakashi has stabbed Rin Nohara right in the heart with Chidori.</p>
<p><strong>This awakens him a 3 tomoe Sharingan, then a Mangekyou Sharingan.</strong></p>
<p>He grows older and masters almost every aspect of his Mangekyou Sharingan, excluding Susano'o. He couldn't use Susano'o because one must achieve a Mangekyou Sharingan in <strong>BOTH EYES</strong> to use it. By the time he awakened his MS, his left eye was in Kakashi and thus couldn't use Susano'o.</p>
<p><strong>Since Obito was injected with tons of Hashirama cells when Madara saved him, they gave him Wood Style, and a Mangekyou Sharingan that never went to blindness.</strong></p>
<p><strong>NOTE: Rin Nohara willingly let Kakashi stab her with Chidori, it was no means of betrayal. She knew that she became Three Tails Jinchuriki and let herself die so she wouldn't rampage in the Leaf Village.</strong></p>
<p>After the Uchiha Annihilation, Obito took the Sharingan of almost every Uchiha Member. So even if he went towards blindness, he could always restock on his hundreds of spares. Not to mention he has a spare Sharingan behind his mask.</p>

CC BY-SA 4.0
2021-04-12T12:50:33.793Z
2021-04-12T12:50:33.793Z
ᴅᴀɴɪᴇʟッ
<p>Considering he have hundreds of spare <em>Sharingan</em> and half body of white zetsu. It is quite easy for him to maintain Mangekyu Sharingan (can never actually use eternal mangekyu).</p>

<p>We can see that in the scene when he transplanted Itachi's eyes to Sasuke.</p>

<p><a href="https://i.sstatic.net/uz3yN.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/uz3yN.png" alt="enter image description here"></a></p>

<p><a href="https://i.sstatic.net/51vkD.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/51vkD.png" alt="enter image description here"></a></p>

CC BY-SA 4.0
2018-05-03T12:37:46.790Z
2018-05-03T13:15:42.167Z
2018-05-03T13:15:42.167Z
ACP
<p>it is due to Hashirama's cells, plus I have always been under the believe that any Uchiha and Senju/Uzumaki pairing would negate any of the physical side effects of the sharingan due to being of the both the physical and spiritual sides of the sage.</p>

<p>it could also have to do with the fact that with one eye missing he can not use susanoo which might have been damaging and intense enough to overwhelm the healing abilities of Hashirama's cells.</p>

CC BY-SA 4.0
2022-03-20T00:29:41.877Z
Not being able to use Susanoo doesn't mean you won't go blind. Sasuke was already starting to go blind after JUST one use of Amaterasu and Kagutsuchi.
Kyle V
CC BY-SA 4.0
2018-06-03T14:13:01.053Z
2018-06-03T14:13:01.053Z
hellfire17
<p>You've all got the wrong idea. It is because he had half of white zetsu's body which was developed using Hashirama's cells. The senju had extremely powerful healing body which could instantly heal any wound. The lost of eyesight occurs due to regular use of the mangekyo sharingan because you don't get the time to heal that injuries done by it in thar sorry period of time, however for Obito because of Hashirama's cells that damage was healed instantly.</p>

CC BY-SA 4.0
2021-01-14T05:25:13.940Z
The other *older* answers state the exact same. It would be noteworthy if you add additional details if you can provide some canonical evidences or instances.
Ero Sɘnnin
CC BY-SA 4.0
2022-03-20T00:28:40.280Z
I agree, as Hashirama's DNA is what allowed Danzo to use Kotoamatsukami once DAILY, instead of waiting 10 YEARS.
Kyle V
CC BY-SA 4.0
2021-01-14T03:31:33.617Z
2021-01-14T03:31:33.617Z
Pushpender Nanda
<p>I could think of two things:</p>

<ul>
<li><p>He was the owner of that Sharingan. He had more compatibility with it. So he can use it more number of times than Kakashi.</p></li>
<li><p>He had Hashirama's cells.</p></li>
</ul>

CC BY-SA 4.0
2022-03-20T00:27:08.540Z
Your first point doesn't make any sense. Madara, Itachi, and Sasuke were the true owners of their Sharingan, and they still went blind from overusing their Mangekyo Sharingan, despite their so-called 'compatibility' with their own true eyes.
Kyle V
CC BY-SA 3.0
2018-04-02T15:18:54.530Z
2018-04-02T23:58:17.590Z
2018-04-02T23:58:17.590Z
virtualvishwam
<p><a href="https://i.sstatic.net/bwSNO.png" rel="noreferrer"><img src="https://i.sstatic.net/bwSNO.png" alt="enter image description here"></a></p>

<p>I've been thinking about his Mangekyo and how it seems to have had no impact on his eye sight and how he could have escaped the effects. After much thought on the topic I think I might have the solution and am wondering if this is a valid theory or not. My theory is you need both Mangekyo to hurt your vision. Since he had only 1 eye this effectively allows him to use part of its power for no effect compared to people like Itachi and Sasuke who do have both and had issues with this. Basically if I didn't make it clear enough with only 1 eye he couldn't get Susanoo or the other great abilities but also didn't have the downside of losing his sight. So do you think this is a valid theory? I know its unprovable either way just trying to see if I'm the only one who thinks this is a possible solution.</p>

CC BY-SA 3.0
2017-09-01T22:20:16.353Z
[Very closely related](https://anime.stackexchange.com/questions/3029/how-does-the-mangekyo-sharingan-blind-its-wielder-and-why-are-some-wielders-not)
Wondercricket
CC BY-SA 3.0
2017-09-02T22:09:48.747Z
I always thought it was because he doesn't use both at the same time like other people, so it would make the eyes last longer. It's only my theory though.
Akira Mahisaseru
CC BY-SA 3.0
2017-09-03T06:52:49.140Z
he had access to lots of sharingans that remained from the uchiha massacre, assuming changing the eye does not take away the original abilities of the user, i'd say he had other eyes implanted in his.
Henjin
CC BY-SA 3.0
2017-09-04T09:06:54.313Z
@Wondercricket Wasn't Kakashi starting to lost his eyesight during the 4th Ninja War near the end (don't know exactly which fight)? I thought Tobi/Obito could use his MS so extensively because he has Hashirama's cells. Just like how Danzo, thanks to Hashirama's cells, didn't have to wait a decade before he could use Kotoamatsukami (Shisui's MS) again.
Gravinco
CC BY-SA 3.0
2017-09-09T04:18:31.483Z
Kakashi was indeed starting to lose his eyesight, almost from the beginning. This is how he knew to ask Itachi about his eyesight, which instantly alerted and shocked Itachi that Kakashi had developed Mangekyou, even though he didn't use it in that fight. There is only one possibility with regard to why Obito didn't lose his sight, despite overuse. Hashirama's cells. We've seen the effect of Hashi's cells revitalizing the Sharingan's ocular powers within Shisui's Mangekyou. It stands to reason that it's possible that it would have a similar effect in staving off Sharingan blindness.
HyperNym
CC BY-SA 3.0
2018-02-26T04:43:12.613Z
I wouldn't call that much use excessive. Plus he had Hashirama's cells, so there's that.
Abhishek Mishra
<naruto>
How does Obito not lose his eyesight after excessive use of the mangekyo?
# How does Obito not lose his eyesight after excessive use of the mangekyo?
Posted by: username_0 on 2017-09-01
[![enter image description here](https://i.sstatic.net/bwSNO.png)](https://i.sstatic.net/bwSNO.png)

I've been thinking about his Mangekyo and how it seems to have had no impact on his eye sight and how he could have escaped the effects. After much thought on the topic I think I might have the solution and am wondering if this is a valid theory or not. My theory is you need both Mangekyo to hurt your vision. Since he had only 1 eye this effectively allows him to use part of its power for no effect compared to people like Itachi and Sasuke who do have both and had issues with this. Basically if I didn't make it clear enough with only 1 eye he couldn't get Susanoo or the other great abilities but also didn't have the downside of losing his sight. So do you think this is a valid theory? I know its unprovable either way just trying to see if I'm the only one who thinks this is a possible solution.
**Tags:** naruto
> **Comments:**
> **username_1**: [Very closely related](https://anime.stackexchange.com/questions/3029/how-does-the-mangekyo-sharingan-blind-its-wielder-and-why-are-some-wielders-not)  
> **username_2**: I always thought it was because he doesn't use both at the same time like other people, so it would make the eyes last longer. It's only my theory though.  
> **username_3**: he had access to lots of sharingans that remained from the uchiha massacre, assuming changing the eye does not take away the original abilities of the user, i'd say he had other eyes implanted in his.  
> **username_4**: @Wondercricket Wasn't Kakashi starting to lost his eyesight during the 4th Ninja War near the end (don't know exactly which fight)? I thought Tobi/Obito could use his MS so extensively because he has Hashirama's cells. Just like how Danzo, thanks to Hashirama's cells, didn't have to wait a decade before he could use Kotoamatsukami (Shisui's MS) again.  
> **username_5**: Kakashi was indeed starting to lose his eyesight, almost from the beginning. This is how he knew to ask Itachi about his eyesight, which instantly alerted and shocked Itachi that Kakashi had developed Mangekyou, even though he didn't use it in that fight. There is only one possibility with regard to why Obito didn't lose his sight, despite overuse. Hashirama's cells. We've seen the effect of Hashi's cells revitalizing the Sharingan's ocular powers within Shisui's Mangekyou. It stands to reason that it's possible that it would have a similar effect in staving off Sharingan blindness.  
> **username_6**: I wouldn't call that much use excessive. Plus he had Hashirama's cells, so there's that.  
---
## 5 answers
### Answer by username_7 on 2021-04-12. Score: 1
To fully answer the question, I'm gonna go back to the Third Great Ninja War, where Obito was a kid.

The Village Hidden in the Leaves is currently at war with the Stone Village, and Team Minato is on the battlefield. Obito and Kakashi are facing a Stone Ninja with camouflage abilities. He uses them and slashes Kakashi's eyes in the process. This leaves Obito crying and awakens his Sharingan. When the invisible Stone Ninja is coming up, Obito uses his Sharingan to track him down, then finishes him with a kunai.

**This is how Obito awakened his Base Sharingan. (2 tomoe)**

The squad of Stone Ninjas have captured Rin Nohara, Obito and Kakashi's third squadmate. After finishing the Stone Ninja, they go to rescue her. They fight with the Stone Ninja, and after, he leaves the area and uses a jutsu to make the cave they fought in collapse. When Rin, Kakashi, and Obito are running away to exit, Kakashi gets hit by a falling rock and falls. Obito then goes back to save him, and gets crushed by a falling boulder. His right side is nearly completely crushed. He gives Kakashi his left eye's Sharingan as a gift for becoming jonin. The remaining members then run for the exit.

By chance, the place Obito was crushed was near an underground passageway that Madara Uchiha created, and Madara then took and healed Obito to use him as his pawn to revive him. While Madara attends to Obito, he injects almost his entire right side with Hashirama Senju's cells, and White Zetsu also attaches himself to Obito's right side.

One of White Zetsu's clones alerts Obito that Rin and Kakashi are in danger and surrounded by Rain Ninja that seemed to be Jonin or Black Ops. Obito then destroys the exit to Madara's lair and runs to aid Rin and Kakashi. By the time he gets there, he sees that Kakashi has stabbed Rin Nohara right in the heart with Chidori.

**This awakens him a 3 tomoe Sharingan, then a Mangekyou Sharingan.**

He grows older and masters almost every aspect of his Mangekyou Sharingan, excluding Susano'o. He couldn't use Susano'o because one must achieve a Mangekyou Sharingan in **BOTH EYES** to use it. By the time he awakened his MS, his left eye was in Kakashi and thus couldn't use Susano'o.

**Since Obito was injected with tons of Hashirama cells when Madara saved him, they gave him Wood Style, and a Mangekyou Sharingan that never went to blindness.**

**NOTE: Rin Nohara willingly let Kakashi stab her with Chidori, it was no means of betrayal. She knew that she became Three Tails Jinchuriki and let herself die so she wouldn't rampage in the Leaf Village.**

After the Uchiha Annihilation, Obito took the Sharingan of almost every Uchiha Member. So even if he went towards blindness, he could always restock on his hundreds of spares. Not to mention he has a spare Sharingan behind his mask.
---
### Answer by username_8 on 2018-05-03. Score: 1
Considering he have hundreds of spare *Sharingan* and half body of white zetsu. It is quite easy for him to maintain Mangekyu Sharingan (can never actually use eternal mangekyu).

We can see that in the scene when he transplanted Itachi's eyes to Sasuke.

[![enter image description here](https://i.sstatic.net/uz3yN.png)](https://i.sstatic.net/uz3yN.png)

[![enter image description here](https://i.sstatic.net/51vkD.png)](https://i.sstatic.net/51vkD.png)
---
### Answer by username_9 on 2018-06-03. Score: 0
it is due to Hashirama's cells, plus I have always been under the believe that any Uchiha and Senju/Uzumaki pairing would negate any of the physical side effects of the sharingan due to being of the both the physical and spiritual sides of the sage.

it could also have to do with the fact that with one eye missing he can not use susanoo which might have been damaging and intense enough to overwhelm the healing abilities of Hashirama's cells.
> **Comments:**
> **username_10** (2022-03-20): Not being able to use Susanoo doesn't mean you won't go blind. Sasuke was already starting to go blind after JUST one use of Amaterasu and Kagutsuchi.  
---
### Answer by username_11 on 2021-01-14. Score: 0
You've all got the wrong idea. It is because he had half of white zetsu's body which was developed using Hashirama's cells. The senju had extremely powerful healing body which could instantly heal any wound. The lost of eyesight occurs due to regular use of the mangekyo sharingan because you don't get the time to heal that injuries done by it in thar sorry period of time, however for Obito because of Hashirama's cells that damage was healed instantly.
> **Comments:**
> **username_12** (2021-01-14): The other *older* answers state the exact same. It would be noteworthy if you add additional details if you can provide some canonical evidences or instances.  
> **username_10** (2022-03-20): I agree, as Hashirama's DNA is what allowed Danzo to use Kotoamatsukami once DAILY, instead of waiting 10 YEARS.  
---
### Answer by username_13 on 2018-04-02. Score: -2
I could think of two things:

* He was the owner of that Sharingan. He had more compatibility with it. So he can use it more number of times than Kakashi.
* He had Hashirama's cells.
> **Comments:**
> **username_10** (2022-03-20): Your first point doesn't make any sense. Madara, Itachi, and Sasuke were the true owners of their Sharingan, and they still went blind from overusing their Mangekyo Sharingan, despite their so-called 'compatibility' with their own true eyes.  
---
