Shi Gai 士匄, also written 士丐, was a nobleman in the state of Jin 晉 during the Spring and Autumn period 春秋 (770-5th cent. BCE). He is also known as Fan Gai 范匄 or whith his posthumous title Fan Xuanzi 范宣子, or Xuan Shu Gai 宣叔匄. He was a grandson of Shi Hui 士會 (Sui Hui 隨會) and a son of Shi Xie 士燮 (Fan Wenzi 范文子), heads of the house of Fan 范, and served Duke Ping 晉平公 (r. 558-532) as a high minister.
When Shi Gai's father died the duke of Jin liked to appoint him general of the Central Army (zhongjun 中軍), but Shi Gai refused, so that Xun Yan 荀偃 was given this post. Shi Gai was finally made assistant commander of the Central Army, a position in which he participated in the successful battle of Yanling 鄢陵 (modern Yanling, Henan) in 575 against the army of Chu 楚. He was therefore promoted to the position of a minister commander (qing 卿).
In 564 he led his battalion for a campaign against the state of Zheng 鄭. The duke of Zheng was threatened and offered peace, which was concluded in the conference of the feudal lords at Xi 戲 (near modern Dengfeng 登封, Henan). Another conference was held in 559 at Qi 戚 (near modern Puyang 濮陽, Henan) during which Duke Shang of Wei 衛殤公 (r. 558-547) was enthroned. When the king of Wu 吳 asked for support against Chu 楚, Fan Xuanzi declined because the state of Chu was in mourning for the recently deceased king.
In 554 Fan Xuanzi replaced Xun Yan 荀偃 as commander of the Central Army (zhongjun shuai 中軍帥), a position that corresponded to counsellor-in-chief. In this position he was able to force the rebellious nobleman Luan Ying 欒盈 into exile and executed his followers. He also introduced a new penal law code (Xingshu 刑書) for the state of Jin that was based on Zhao Dun's 趙盾 (Zhao Xuanzi 趙宣子) "standard rules" (changfa 常法). This code was later promulgated, incised in a bronze tripod.