Tamil cinema (also known as the Kollywood, the Tamil film industry, the Cinema of Tamil Nadu or the Chennai film industry) is the film industry based in Chennai, Tamil Nadu, India, dedicated to the production of feature films in the Tamil language. It is based in Chennai's Kodambakkam area, where several South Indian film production companies are headquartered. With reference to this, the industry is also colloquially referred to as Kollywood, a portmanteau of Kodambakkam and Hollywood. Tamil cinema is known for being India's second largest film industry in terms of films produced, revenue and worldwide distribution, with audiences mainly including people from the four southern Indian states of Tamil Nadu, Kerala, Andhra Pradesh, and Karnataka, placing the industry among the largest in the world.

Silent films were produced in Chennai since 1917 and the era of talkies dawned in 1931 with the film Kalidas. By the end of the 1930s, the legislature of the State of Madras passed the Entertainment Tax Act of 1939. Tamil cinema later had a profound effect on other filmmaking industries of India, establishing Chennai as a secondary hub for Telugu cinema, Malayalam cinema, Kannada cinema, and Hindi cinema. In its modern era, Tamil films from Chennai have been distributed to various overseas theatres in Singapore, Sri Lanka, South Africa, Malaysia, Japan, Oceania, the Middle East, Western Europe, and Northern America. The industry also inspired filmmaking in Tamil diaspora populations in other regions, such as in Europe and Canada.