Yamaya Tanin (山屋 他人, April 18, 1866 – September 10, 1940) was a naval theorist and admiral in the Imperial Japanese Navy during the early twentieth century.

During the First Sino-Japanese War, Yamaya was chief navigator on the converted passenger liner Saikyo-maru, and was present during the Battle of the Yalu on September 17, 1894, when the ship was commanded by the belligerent Admiral Kabayama Sukenori.

Sakamoto chose Yamaya (along with Akiyama Saneyuki) as part of a "brain trust" and assigned him the task of making a comprehensive survey of methods and developments at the naval colleges of various western powers.

[2] He was awarded the Navy Distinguished Service Medal by the United States government for his contributions to the Allied effort in World War I.

[3] Recalled to Japan the following year, Yamaya was appointed Vice Chief of the Imperial Japanese Navy General Staff, where he served until 1918, when he was given command of the 2nd Fleet.