Guilan (گیلان in Persian) is one of the 30 provinces of Iran, during antique time known as part of Hyrcania, with a population of approximately 2 million and an area of 14,700 sq. km. It lies just west of the province of Mazandaran, along the Caspian Sea. The center of the province is the city of Rasht.

The main harbor is Bandar-e Anzali (previously Bandar-e Pahlavi).

The majority of the population speaks as first language Gilaki, a dialect of Persian while many children especially in the cities tend to use the standard Persian among themselves.

The main tourist attraction is the small town of Massouleh in the hills south-east of Rasht. The town is build similar to a pueblo with the roof of one house being the courtyard of the next house.

Large parts of the province are mountainous, green and forested.The coastal plain along the Caspian Sea is - similar to that of Mazandaran mainly used for rice paddies.

The province has its own Radio and TV programme.

In May 1990 large parts of the province were destroyed by a huge earthquake, in which about 50.000 to 100.000 people died. About that event Abbas Kiarostami made his famous films "Nothing but life" and "Through the olive-trees"