Jia Ji 賈季, also called Jia Ta 賈他, was a nobleman in the state of Jin 晉 during the Spring and Autumn period 春秋 (770-5th cent. BCE). He was commander of the Central Army (zhongjun shuai 中軍帥) under Duke Xiang of Jin 晉襄公 (r. 628-621) but was degraded after Yang Chu Fu 陽處父 had inspected the troops of Jin. He therefore orded his retainer Ju Ju 鞫居 to kill Yang Chu Fu.
When Duke Xiang died, a succession crisis befell the house of Jin. Zhao Dun 趙盾 (Zhao Xuanzi 趙宣子) planned to enthrone Prince Yong 雍, a younger brother of the late Duke, because his son, Prince Yigao 夷皋, was still a child. Yet Jia Ji preferred Prince Le 樂, another brother of Duke Xiang. Zhao Dun proved the stronger, had Jia Ji dismissed and forced into exile among the Di tribes 翟.