Hayashi Hidesada (林 秀貞, 1513 – November 21, 1580) was a Japanese samurai and retainer of Oda clan, who lived during the Sengoku period.

The Hayashi family, a branch of the Inaba clan, originated from the village of Oki in the Kasugai District of Owari Province.

In 1556, Hidesada together with Shibata Katsuie gathered troops to oust Nobunaga and replace him with Oda Nobuyuki.

They lost in the Battle of Inō and a temporary truce was brokered by Nobunaga, who did not want to continue a fight that might draw an invasion from neighboring daimyōs.

In August 1580, Nobunaga suddenly decided to banish Hidesada from all positions for having supported Nobuyuki in the past.