Kōzōsu (孝蔵主) was a Japanese noble lady, aristocrat and retainer of the Toyotomi clan. She was the daughter of , a retainer of the Gamō clan. She was an elite female officer under Nene's command and chief secretary to Toyotomi Hideyoshi. During the Toyotomi administration she possessed such authority that it was said that while Asano Nagamasa may run matters outside, Kōzōsu ran matters inside. She accompanied the Toyotomi clan in Japan's unification campaigns.