He was killed in a purge of high-level Tang officials by the warlord Zhu Quanzhong the military governor (jiedushi) of Xuanwu Circuit (宣武, headquartered in modern Kaifeng, Henan), who was then preparing to seize the throne.
Early in Emperor Zhaozong's Dashun era (890–891), Cui, while carrying the relatively low title of Yuanwailang (員外郎), became a drafter of imperial edicts.
He thereafter was made deputy minister of defense (兵部侍郎, Bingbu Shilang) and chief imperial scholar (翰林學士承旨, Hanlin Xueshi Chengzhi).
[3] In late 896, Emperor Zhaozong gave Cui Yuan the designation Tong Zhongshu Menxia Pingzhangshi (同中書門下平章事), making him a chancellor.
[4] Thereafter, his other offices became Zhongshu Shilang (中書侍郎), the deputy head of the legislative bureau, and the minister of civil service affairs (吏部尚書, Libu Shangshu).
At that time, Cui and the other chancellors Pei Shu and Dugu Sun all were senior officials who came from aristocratic families, and they despised their colleague Liu for associating with Zhu.
Zhu thus had all three removed from chancellor positions; in Cui's case, he was made Zuo Pushe (左僕射), one of the heads of the executive bureau (尚書省, Shangshu Sheng).