The Chōkai Sanroku Line (鳥海山ろく線, Chōkai Sanroku-sen, "Chōkai Submontane Line") is a Japanese railway line in Akita Prefecture in northern Japan, with all station located within the city of Yurihonjō.

On August 1, 1922, the privately owned Yokote Railway Company (横手鉄道, Yokote Tetsudō) completed its West Line, connecting Ugo-Honjō with Maegō over 11.6 rail kilometers, and renamed itself the Yokojō Railway Company (横荘鉄道, Yokojō Tetsudō).

The line was further extended an additional 7.3 kilometers to its present terminus at Yashima by October 21, 1938.

The JGR became the Japanese National Railways (JNR) after World War II.

[citation needed] In 1985, the operations of the former Yashima Line were taken over by the third sector company Yuri Kōgen Railway.