Hayashi Hidesada (林 秀貞, 1513 – November 21, 1580) was a Japanese samurai and retainer of Oda clan, who lived during the Sengoku period. He was also known as Michikatsu (通勝). His court title was Governor of Sado Province (Sado no Kami). The Hayashi family, a branch of the Inaba clan, originated from the village of Oki in the Kasugai District of Owari Province.