Gamō Yorisato served as a bushō during the Azuchi-Momoyama period. His true name was Sanenori and common name of Kinai. He carried the title of Governor of Bitchū.
Yorisato came from the village of Yokoyama in Hino in the Gamō District of Ōmi Province. His first name was Yokoyama Kinai. Initially, he served as a retainer of the Rokkaku clan, but during Oda Nobunaga’s march upon the capital of Kyōto, the Rokkaku were eliminated so he served the Gamō clan. In 1582, after the coup d’état against Oda Nobunaga known as the Honnō-ji Incident, he holed-up in Hino Castle. In 1587, Yorisato participated in the Subjugation of Kyūshū led by Toyotomi Hideyoshi, serving as a military magistrate for the attack on Ganjaku Castle. After the war, he received one of the characters in his name from his lord, Gamō Ujisato, and adopted the name of Gamō Yorisato. After Ujisato moved to Aizu in Mutsu Province, Yorisato served as the chamberlain of Shiokawa Castle with a fief of 13,000 koku. Later, he served as the chamberlain of Yanagawa Castle.
After Gamō Hideyuki was reassigned to Utsunomiya in Shimotsuke Province, Yorisato fled and served Ishida Mitsunari.
In 1600, Yorisato joined the Western Army and, together with Shima Kiyoaki, fought valiantly at the Battle of Sekigahara. Amidst unfavorable circumstances, he injured Oda Nagamasu (a daimyō and son of Oda Nobuhide), but was then killed in action by a retainer of Nagamasu named Chiga Bunzō and his brother, Chiga Bunkichi.