Kuniyoshi was the 7th son of Ishikawa Yoshimitsu, the 13th hereditary chieftain of the Ishikawa clan, a cadet branch of the Date clan of Sendai Domain.

In 1868, he obeyed the call of Sendai Domain, and led Ichinoseki troops into the Ōuetsu Reppan Dōmei against the new Meiji government in the Boshin War.

Kuniyoshi retired in favor of his younger brother, Tamura Takaaki.

In 1869 his court rank was increased to Fifth Grade, and he served the new government in various capacities.

In 1882, the chieftainship of the Tamura clan was returned from his brother, and in 1884 he was ennobled with the kazoku peerage title of shishaku (viscount).