It said the group sought to recruit people through the Internet for training in Iraq with the People's Mujahideen Organization, a leftist exile group which launched attacks on the Islamic Republic from Saddam Hussein's Iraq.
"Thirty people were arrested in connection with an organized American cyber war network via a series of complex security measures in the field of information technology and communications," the Fars news agency said.
Tehran's general and revolutionary court said one of the group was linked to an outlawed sect -- a reference to the Baha'i religious minority, the agency said.
"Among the charges against this network are creating an intelligence gathering network, including identification of the country's nuclear scientists and staging illegal demonstrations and encouraging the public to take part in them after the presidential elections," it said.
Iran has seen its biggest domestic crisis since the 1979 revolution as supporters of candidates who lost to President Mahmoud Ahmadinejad last year took to the streets in protests, provoking a strong security clampdown.
Iran is locked in a dispute with Western countries who fear its nuclear energy program is a front for developing nuclear weapons. Washington and its allies have condemned Iran for its treatment of the opposition movement.