Wongwian Yai railway station is a railway station located in Bang Yi Ruea subdistrict, Thon Buri district, Bangkok. It is a class 1 railway station and is the Bangkok terminus of the Maeklong Railway Mahachai Line. Currently, 34 rail services operate at the station. It is located closer to Wongwian Yai roundabout and is in a different location to Wongwian Yai BTS station. Wongwian Yai is the main station used for rail passenger traffic from Samut Sakhon and Samut Songkhram provinces. It is the only railway station terminus with a single track in Thailand.

Wongwian Yai is planned to be a station on the SRT Dark Red Line extension to Mahachai.

The station opened on 29 December 1904 during the reign of King Chulalongkorn, as part of the Pak Khlong San–Mahachai railway operated by the Tachin Railway Ltd. On 24 November 1959, Prime Minister Sarit Thanarat suggested to the cabinet that the Pak Khlong San–Wongwian Yai section be closed in order to accommodate the increase in road traffic. The station became the line's terminus following the closure of Pak Khlong San railway station, on 1 January 1961, with the Pak Khlong San–Wongwian Yai section converted into Charoen Rat Road.

On 22 March 2019, a train collided with the buffer stop at Wongwian Yai station due to an air brake failure. Two people were injured.

13°43′29″N 100°29′31″E / 13.7247°N 100.4919°E / 13.7247; 100.4919