Duke Xiao (孝公) (381 - 338 BC), born Ying Quliang (嬴渠梁), was a ruler of the State of Qin from 361 to 338 BC during the Warring States Period in China. He employed Shang Yang, a skilled official from Wei who made two sets of political reforms to strengthen Qin. Qin rewarded soldiers land and slaves based on achievement.

He is the last duke of Qin. After him, the Qin rulers were kings until the first emperor, Qin Shi Huangdi.

His posthumous name Xiao means "filial".