  We present the discovery of the first Neptune analog exoplanet or super-Earth
with Neptune-like orbit, MOA-2013-BLG-605Lb. This planet has a mass similar to
that of Neptune or a super-Earth and it orbits at $9\sim 14$ times the expected
position of the snow-line, $a_{\rm snow}$, which is similar to Neptune's
separation of $ 11\,a_{\rm snow}$ from the Sun. The planet/host-star mass ratio
is $q=(3.6\pm0.7)\times 10^{-4}$ and the projected separation normalized by the
Einstein radius is $s=2.39\pm0.05$. There are three degenerate physical
solutions and two of these are due to a new type of degeneracy in the
microlensing parallax parameters, which we designate "the wide degeneracy". The
three models have (i) a Neptune-mass planet with a mass of $M_{\rm
p}=21_{-7}^{+6} M_{Earth}$ orbiting a low-mass M-dwarf with a mass of $M_{\rm
h}=0.19_{-0.06}^{+0.05} M_\odot$, (ii) a mini-Neptune with $M_{\rm p}=
7.9_{-1.2}^{+1.8} M_{Earth}$ orbiting a brown dwarf host with $M_{\rm
h}=0.068_{-0.011}^{+0.019} M_\odot$ and (iii) a super-Earth with $M_{\rm p}=
3.2_{-0.3}^{+0.5} M_{Earth}$ orbiting a low-mass brown dwarf host with $M_{\rm
h}=0.025_{-0.004}^{+0.005} M_\odot$ which is slightly favored. The 3-D
planet-host separations are 4.6$_{-1.2}^{+4.7}$ AU, 2.1$_{-0.2}^{+1.0}$ AU and
0.94$_{-0.02}^{+0.67}$ AU, which are $8.9_{-1.4}^{+10.5}$, $12_{-1}^{+7}$ or
$14_{-1}^{+11}$ times larger than $a_{\rm snow}$ for these models,
respectively. The Keck AO observation confirm that the lens is faint. This
discovery suggests that low-mass planets with Neptune-like orbit are common. So
processes similar to the one that formed Neptune in our own Solar System or
cold super-Earth may be common in other solar systems.
