What form of government does Iran have?

Iran's government is defined as a theocratic republic. A theocracy is ruled by religious leaders who are believed to be acting on behalf of their deity. A republic is run by a democratically elected leader. In Iran, the government is run by an elected president, parliament, local councils and an "Assembly of Experts"- all of which must follow Islamic principles.

The government in Iran is a unitary state with a presidential system. The capital of Iran is Tehran, and has a population of 76.42 million.

Because of its theocratic elements, Iran is typically considered an Illiberal Democracy (as opposed to Liberal Democracies like the United States, France, Germany, et al.). That is to say that while there are certain trappings of democracy, they are not sufficient to create a truly democratic atmosphere. Several things that Iran has which make it a democracy include: regular voting periods, different candidates, and different parties with conflicting interests. Several things that Iran has, which preclude it from being a Liberal Democracy include: suppression of political expression, unelected leadership (in the form of the Supreme Leader and his council), repression of political parties, widespread voting fraud, restrictions on the freedom of speech and in the press, required loyalty oaths (this prevents members of Parliament from speaking out on issues for minority constituencies which have been harassed by the government), and unbalanced campaigning (where the "desirable" candidate can slander other candidates, but cannot himself be publicly slandered to the same extent).
Iran has a mixed econmy.