Mù Cang Chải is a rural district of Yên Bái Province, in the Northeast region of Vietnam. As of 2003, the district had a population of 42,574. The district covers an area of 1,199 km². The district capital lies at Mù Cang Chải.
Mu Cang Chai is a district of Yen Bai province, it shares the border in the north with Van Ban district of Lao Cai province, neighboring in the south of Muong La district of Son La province, being the west of Than Uyen Lai Chau province, sharing in the east of Van Chan district and Yen Bai province. The district is located at the foot of Hoang Lien Son mountain range, at an altitude of 1,000 m above sea level. Want to get Mu Cang Chai district, traveler will go through Khau Pha Pass that is one of the four imposing passes in the Northwest of Vietnam.