Duke Huan of Qin (Chinese: 秦桓公; pinyin: Qín Huán Gōng, died 577 BC), personal name Ying Rong, was from 603 to 577 BC the ruler of the Qin state.
[1][2] In 578 BC, Qin suffered a major defeat at the hand of the Jin state.
Duke Li of Jin accused Qin of treachery and personally led an alliance of eight states (Jin, Qi, Song, Wey, Zheng, Cao, Zhu, and Teng) to attack Qin.
The two sides fought at Masui (in present-day Jingyang County, Shaanxi).
Qin was resoundingly defeated and two of its generals were captured, although Duke Xuan of Cao, ruler of Jin's ally Cao, was also killed in the battle.