Chennai Metro is a rapid transit system serving the city of Chennai, India. As of April 2024, the operational network consists of two colour-coded lines covering a length of 54.1 km (33.6 mi) making it the fifth longest metro system in India. Chennai Metro Rail Limited (CMRL), a joint venture between Government of India and the Government of Tamil Nadu built and operates the Chennai Metro. The system uses standard gauge and has a mix of underground and elevated stations.

Urban rail transit in India plays an important role in intracity transportation in the major cities which are highly populated. It consists of rapid transit, suburban rail, monorail, and tram systems.