A prominent literatus and member of a prestigious aristocratic clan, Pei was considered a capable administrator and was credited with the skillful management of the Tang government's salt and iron monopoly.
Pei was also a dedicated practitioner and patron of Chan Buddhism, pursuits which drew critique from later Confucian historians.
Early in the Taihe era (827–835) of Emperor Muzong's son Emperor Wenzong, he served on the staffs of several regional governors, and he was at one point recalled to the capital Chang'an to serve as an imperial censor with the title Jiancha Yushi (監察御史); You Bujue (右補闕), an advisory official at the legislative bureau of government (中書省, Zhongshu Sheng); and an editor of imperial history.
[2] As of 851, during the reign of Emperor Wuzong's uncle Emperor Xuānzong, Pei Xiu was serving as the deputy minister of defense (兵部侍郎, Bingbu Shilang), when he was also made the director of salt and iron monopolies, who was also responsible for overseeing the food supply shipments from the Yangtze River–Huai River region to Chang'an and the eastern capital Luoyang.
It was said that, by that time, due to various shipping problems that had developed over the decades since the capable chancellor Liu Yan, who died in 780, the supply of rice from the Yangtze-Huai region had dwindled to 400,000 Hu (斛) per year.
[2] In 852, by which time Pei had been made the minister of rites (禮部尚書, Libu Shangshu), he was also given the designation Tong Zhongshu Menxia Pingzhangshi (同中書門下平章事), making him a chancellor de facto.
[4] Yet later that year, Emperor Xuānzong gave him the honorary titles Jinzi Guanglu Daifu (金紫光祿大夫) and Shang Zhuguo (上柱國), and created him the Viscount of Hedong, but further removed him from being the military governor of Xuanwu, instead making him an advisor to the crown prince—an entirely honorary title as there was still no crown prince at the time—with his office at Luoyang.
[2] In 857, Pei was made the military governor of Zhaoyi Circuit (昭義, headquartered in modern Changzhi, Shanxi).