Abstract: From March 2020 to November 2022, infrared cameras were used to continuously monitor large and medium-sized mammals and bird species in the underforest of Tangjiahe National Nature Reserve in Sichuan Province, with a total of 386 monitoring sites deployed. 37,981 independent and effective records were obtained in 137,200 effective camera working days, and 26 species of wild mammals and 53 species of wild birds were identified. Among them, there are 5 mammals and 2 birds under national level I key protection, 9 mammals and 10 birds under national Level II key protection. There are two species on the IUCN Red List that are endangered (EN), six species vulnerable (VU) and four species near threatened (NT). There are 7 species of mammals and 6 species of birds unique to China. Based on the relative abundance index (RAI) and site occupancy (SO), Chinese Takin (Budorcas tibetana) (RAI=9.8622; SO=93.78%), Chinese Muntjac (Muntiacus reevesi) (RAI=3.9978; SO=60.10%), Wild Boar (Sus scrofa) (RAI=2.7442; SO=88.34%), Chinese Goral (Naemorhedus griseus) (RAI=2.4235; SO=80.83%), Temminck’s Tragopan (Tragopan temminckii) (RAI=0.6655; SO=26.94%) were ranked as the 5 most abundant mammal and bird species. Meanwhile, five bird species including Tibetan Snowcock (Tetraogallus tibetanus), Alström's Warbler (Phylloscopus soror), Alpine Thrush (Zoothera mollissima)、Eyebrowed Thrush (Turdus obscurus)、Himalayan Bush-robin (Tarsiger rufilatus) were new records in the nature reserve. The mammal species richness was high in different functional zones and different regional locations of the reserve, while the bird species richness was high in the core area. The results of this study indicate that the reserves are rich in rare and endangered wildlife resources, and it is necessary to continuously strengthen scientific research monitoring and protection management. It is suggested to strengthen the monitoring of the uncovered areas, and strengthen the evaluation of the health degree and stability of the ecosystem in this nature reserve.