[8][9] After Li Fengji passed the imperial examinations, the general Fan Xichao (范希朝) invited him to serve as a scribe on his staff when Fan served as the military governor (jiedushi) of Zhenwu Circuit (振武, headquartered in modern Hohhot, Inner Mongolia).
[10] Fan subsequently recommended Li Fengji to then-reigning Emperor Dezong (Emperor Suzong's grandson), and Li Fengji was made a Zuo Shiyi (左拾遺), a low-level consultant at the examination bureau of government (門下省, Menxia Sheng).
[8] He was later promoted to Zuo Bujue (左補闕), also consultant at the examination bureau, and then made an imperial censor with the title Shiyushi (侍御史).
[4][12][13] After Li Fengji returned from the mission in 809, he was made Cibu Langzhong (祠部郎中), a supervisorial official at the ministry of rites (禮部, Libu), and later Yousi Langzhong (右司郎中), a supervisorial official under the secretaries general of the executive bureau (尚書省, Shangshu Sheng).
Later that year, he was made Menxia Shilang (門下侍郎), the deputy head of the examination bureau, and de facto chancellor with the title Tong Zhongshu Menxia Pingzhangshi (同中書門下平章事); he was also given the honorary title of Chaoyi Daifu (朝議大夫).
Emperor Xianzong agreed, and ordered the troops then attacking Chengde to withdraw back to their own circuits.
Later in the year, both because of Li Fengji's disagreements with Pei, whom Emperor Xianzong trusted, and because Emperor Xianzong wanted to commission an associate of his while he was still an imperial prince, Zhang Su (張宿), as a high-level consultant and Li Fengji strenuously objected, Emperor Xianzong sent Li Fengji out of the capital Chang'an, making him the military governor of Dongchuan Circuit (東川, headquartered in modern Mianyang, Sichuan.
[15] After Emperor Xianzong died in 820 and was succeeded by Li Heng (as Emperor Muzong), Li Fengji was moved to be the military governor of Shannan East Circuit (山南東道, headquartered in modern Xiangfan, Hubei) as well as the prefect of its capital Xiang Prefecture (襄州).
Li Fengji thus suggested summoning Li Jie to serve as an imperial guard general, while transferring Han Chong (韓充) the military governor of Yicheng Circuit (義成, headquartered in modern Anyang, Henan), whose brother Han Hong had served as Xuanwu's military governor for a long period, to Xuanwu.
[16] Late in the year, after Emperor Muzong suffered a stroke after being shocked by the fall of an eunuch at a polo game, it was at Li Fengji's and Pei's request that Emperor Muzong created his oldest son Li Zhan the Prince of Jing as crown prince.
Per regulations at the time, when the mayor of Jingzhao Municipality (京兆, i.e., the Chang'an region) were commissioned, he were to report to the office of the imperial censors to pay homage.
Before Emperor Jingzong formally took the throne, Li Fengji served as regent for three days.
When Wei pointed this out, Emperor Jingzong revised the edict to allow such movements, and Li Shen thus was moved closer to the capital to serve as the secretary general of Jiang Prefecture (江州, in modern Jiujiang, Jiangxi).
In the subsequent investigation, Li Zhongyan's attempt to induce Mao to bear false testimony was revealed.
In winter 826, Li Fengji was sent out of the capital to again serve as the military governor of Shannan East Circuit, carrying an honorary chancellor title.
In 831, he was made the defender of the eastern capital Luoyang and given honorary titles as senior advisor to the Crown Prince[20] and Kaifu Yitong Sansi (開府儀同三司).