Qu Gai 屈匄 (d. 312 BCE), also written 屈丐, was a general of the state of Chu 楚 in the Warring States period 戰國 (5th cent.-221 BCE). Qu hailed from Wei 魏 and served for some time the King Huiwen 秦惠文王 (r. 338-311) of Qin, where he made the acquaintence of the famous diplomatist Zhang Yi 張儀.
Zhang Yi went to Chu, where he advised King Huai of Chu 楚懷王 (r. 329-299) to break off the alliance with Qi 齊 and establish good relationships with Qin. Qin would be willing to give up some territory as a pledge for the alliance. Chen Zhen 陳軫 warned the king to break the alliance with Qi, but in vain. When the territory was not released by Qin after some time and instead given to Qi, the new ally of Qin, King Huai decided to declare war on Qin.
The king ordered Qu Gai to take over command of the army of Chu, which met the army Qin under Shuzhang Zhang 庶長章 (Wei Zhang 魏章) in the battle of Danyang 丹陽 (today's Danshui 丹水, Henan). Chu was defeated and lost no less than 80,000 armoured infantry (jiashi 甲士). Qu Gai, his lieutentant general (baijiang 裨將, pian jiangjun 偏將軍) Feng Houchou 逢侯丑 and many officers were captured, and the territory of Hanzhong 漢中 was lost to Qin.
King Huai thereupon shuffled together his last troops, threw them against Qin, but was once more defeated in the battle of Lantian 蘭田 (today in Shaanxi). In this situation, the states of Han 韓 and Wei invaded Chu and occupied several towns. This was the end of Chu as a strong power in south China.
When King Wu 秦武王 (r. 311-307) mounted the throne in Qin, Qu Gai and Zhang Yi were forced to leave Qin and returned to Wei.