The line runs from the centre of Toyohashi, traversing the centre of the Atsumi Peninsula, a largely rural district noted also for its hot spring resorts and marine sports as part of Mikawa Wan Quasi-National Park.

Construction of a proposed extension to Mikawa Fukue commenced in 1939, but was later abandoned due to World War II.

The section between Mikawa Tahara and Kurokawahara and many stations were suspended on June 5, 1944, as an austerity measure.

[6][7] Three P-51 Mustang aircraft attacked a train heading to Toyotashi on August 14, 1945, killing 15 people and injuring an additional 16.

[9] As of April 2015[update], the line is operated using a fleet of ten three-car 1800 series electric multiple unit (EMU) trains.