He hailed from the commandery of Nanyang 南陽 (today in Hebei) and, as a boy, accompanied his father into the province of Yizhou 益州 (Sichuan). Lü loved books and playing the zither.
When the warlord Liu Bei 劉備 (161-222) conquered Yizhou, Lü was invited by Wang Liang 王連, who recommended him for promotion, so Lü Yi was made commandant of military and government supplies (diancao duwei 典曹都尉), being responsible for the local state monopoly over salt and iron. The next steps of career was district magistrate (ling 令) of Xindu 新都, and then of Mianzhu 綿竹. His effective and popular mode of governance earned Lü Yi the post of governor (taishou 太守) of the critical border commandery of Hanzhong 漢中, a function in which he had to care for the military supply for troops campaigning against the empire of Wei 曹魏 (220-265). He was later transferred to the commandery of Guanghan 廣漢, and then to the metropolitan commandery of Shujun 蜀郡. In 246, Lü Yi succeeded Dong Yun 董允 (d. 246) as Director of the Imperial Secretariat (shangshu ling 尚書令).
Book catalogues record a 15-chapters-long text written by him called Gelun 格論 "Discussion on regulations".