), courtesy name Biaochen (表臣), formally Duke Miu of Pengyuan (彭原繆公), was an official of the Chinese Tang dynasty, serving as a chancellor during the reign of Emperor Jingzong.
In 815, he was recalled to Chang'an to serve as the deputy minister of defense (兵部侍郎, Bingbu Shilang) and also became in charge of drafting imperial edicts.
At a later point, he was recalled to serve as the deputy minister of civil service affairs (吏部侍郎, Lìbu Shilang, note different tone), and created the Baron of Weiyuan.
He was soon made Zhongshu Shilang (中書侍郎), the deputy head of the legislative bureau, and created the greater title of Duke of Pengyuan, while continuing to serve as chancellor.
[5] In 826, Li Cheng was relieved of his post as chancellor (although he continued to hold the Tong Zhongshu Menxia Pingzhangshi designation as an honorary title), and made the military governor of Hedong Circuit (河東, headquartered in modern Taiyuan, Shanxi), as well as the mayor of its capital Taiyuan Municipality.
Soon thereafter, he was recalled to Chang'an to serve as Zuo Puye (左僕射), one of the heads of the executive bureau (尚書省, Shangshu Sheng).
[3][6] Meanwhile, it was said that Li Cheng was talented and learned, but was seen as frivolous, careless, and overly humorous, and therefore did not have a good reputation despite his high position.
In 836, he was recalled to Chang'an to serve as You Puye (右僕射), the other head of the executive bureau, as well as acting minister of worship (太常卿, Taichang Qing).
He soon thereafter also assumed the post of acting minister of civil service affairs (吏部尚書, Libu Shangshu) and was in charge of selecting officials.
In 837, he was sent out to serve as the military governor of Shannan East Circuit (山南東道, headquartered in modern Xiangfan, Hubei) and the prefect of its capital Xiang Prefecture (襄州), carrying the acting Situ title.