During the reign of Duke Huan 齊桓公 II (r. 384-379), he acted as grand master (dafu 大夫). In 370, when the armies of Qin 秦 and Wei 魏 attacked the state of Han 韓, he suggested to the duke supporting Han and to use the chance to pursue the former attacks on the state of Yan 燕. In fact, the army of Qi was able to conquer some territory of Yan.
On the accession of the heir, King Wei 齊威王 (r. 378-343), Zou Ji escaped being fired by performing a music play to the king with drums and zither. In 358, he was made Counsellor-in-chief and was enfeoffed with the town of Xiapei 下邳 (modern Peixian 邳縣, Jiangsu) with the posthumous title of Marquis Cheng 成侯.
Zou Ji advocated a reform of the government, with a strong accent on laws and models, the selection of worthies as advisors instead of relatives to the ruling house, and a reform of the military. He was the initiator of the plan to encircle the state of Wei 魏 in order to relieve Zhao. His last years were overshadowed by the conflict with general Tian Ji 田忌.