The Shahab-3 is thought capable of striking Israel
The missiles included the Shahab-3, which has a 2,000km (1,240 mile) range, and the Shahab-2, which can carry cluster bombs, the report said.
Analysts say the Shahab-3 is capable of hitting Israel and US military bases in the Gulf.
The missile tests come at the start of 10 days of military manoeuvres planned across the country.
On Wednesday, the head of Iran's Revolutionary Guard, General Yahya Rahim Safavi, said the exercises, named "Great Prophet", would take place in the Gulf, the Gulf of Oman and several provinces of the country.
Gen Safavi said the exercises would be a show of defensive capability.
One report said the missiles fired on Thursday were launched from the desert near the clerical centre of Qom, 120km (75 miles) south of Tehran.
The military manoeuvres come as the UN Security Council is considering putting sanctions on Iran in response to its refusal to stop enriching uranium.
Western countries fear Iran is trying to develop a nuclear bomb, but Iran maintains its nuclear programme is for entirely civilian purposes.
Iran's Revolutionary Guards began another series of military exercises on Thursday days after a United States-led naval exercise began in the Persian Gulf.
Iran began the 10 days of manoeuvres in the Persian Gulf by test firing dozens of missiles, including the long-range Shahab-3 (estimated range: 2000 km or 1,240 miles), Iranian state-run television said on Thursday. Amongst other weapons tested was the Shahab-2, which Iran says can carry a cluster warhead that can deliver 1,400 bomblets at once. 

Major General Yahya Rahim Safavi, leader of the Revolutionary Guards, said on television that Iran's military exercises were not meant to threaten neighbouring countries. "We want to show our deterrent and defensive power to trans-regional enemies, and we hope they will understand the message of the manoeuvres," he said. "The first and main goal is to demonstrate the power and national determination to defend the country against possible threat."
General Safavi said the exercises would last 10 days and would take place in the Persian Gulf, the Gulf of Oman and several Iranian provinces.