Abstract: From October 2020 to June 2021, bird diversity was investigated by the method of sample line, sample point and infrared camera technology in Xionglongxi Provincial Nature Reserve, Sichuan Province. Based on field investigation and 2008 scientific review report, a total of 187 birds （145 species obtained in the field） belonging to 46 families and 15 orders were recorded in the reserve. In which, there were 116 resident birds （62.03%）, 42 summer migratory birds （22.46%）, 19 winter migratory birds （10.16%） and 10 migratory birds （5.35%）. Fauna analysis indicated that, among the breeding birds, 87 were from Palearctic Realm （46.52%）, 80 were from Oriental Realm （42.78%） and 20 were widespread species （10.70%）. Of all the 187 bird species, there were 7 class I and 30 class II national key protected birds, and 6 Sichuan provincial key protected species. Eight of them were listed in the IUCN Red List with 2 Endangered, 1 Vulnerable and 5 Near Threatened. 3 species were listed on CITES Appendix Ⅰ and 12 species were listed on CITES Appendix Ⅱ. Moreover, 13 species were found to be endemic in China. The results showed that the species richness of alpine shrub meadows was the highest, the Shannon-Wiener index of broad-leaved forest was the highest, while the species richness and Shannon-Wiener index of the screes were the lowest. Except for alpine screes habitat, the similarity of the other five habitats was high （IsJ=0.234~0.352）, among which the similarity between water area and coniferous forest was the highest （IsJ=0.352）. In different seasons, the number of birds species, Shannon-Wiener index and Pielou evenness index in breeding season were higher than those in non-breeding season. The vertical distribution pattern of bird species number and community diversity index showed a mid-altitude peak pattern in different seasons, and the highest peak was concentrated at 3650-3850m. On the whole, the nature reserve is rich in bird diversity, especially in rare, endangered and endemic birds, which is important for ecological protection and scientific research management. It is recommended to strengthen the monitoring of rare bird species, strengthen the protection of water areas and other habitats, and strengthen the publicity, education and law enforcement of birds protection.