Marina South MRT station is a non-operational underground Mass Rapid Transit station on the Thomson–East Coast line. Situated in Straits View and Marina South, Singapore, it is located close to Marina South Pier. First announced in August 2012 as part of the Thomson line (TSL), the station was constructed as part of TEL Phase 3 (TEL3) with the merger of the TSL and the Eastern Region line (ERL).

The Thomson–East Coast Line (TEL) is a high-capacity Mass Rapid Transit (MRT) line in Singapore. Coloured brown on the rail map, it is fully underground. When fully completed, the sixth line on the country's MRT network will serve 32 stations around 43 kilometres (27 mi) in length, becoming one of the world's longest driverless rapid transit lines. It runs along a combined north–south and east–west corridor, starting in the north at Woodlands town, passing through Upper Thomson and the towns of Ang Mo Kio and Bishan, heading south to the city-centre at Orchard Road and Marina Bay, subsequently heading eastwards along the eastern coast of the country through Kallang, Marine Parade and southern Bedok before ending at Upper East Coast.