[Objectives] Alpine ecosystems are usually highly biodiverse and vulnerable to environmental changes, the distribution and conservation of species in these ecosystems are of great concern. Seasonal variation in community composition and species distributional ranges along alpine ecosystems are essential to inform conservation, however, remain poorly understood. The Gaoligong Mountains, one of the global biodiversity hotspots in SW China, home to various endemic groups of plants and animals, have been widely acknowledged for their high biodiversity. This study aims to understand how seasonal and monthly variation and activity regularity of large and medium-sized mammals and ground-living birds in alpine ecosystems at the Gaoligong Mountains using infrared cameras. We also compare the species composition of birds and mammals at diverse alpine ranges. [Methods] In the present study, we conducted surveys of birds and mammals using camera traps in the alpine areas (elevation ranges: 3 100﹣3 700 m) in the southern section of the Gaoligong Mountains from November 2018 to October 2019. A total of 60 infrared cameras were employed in three locations, including Nanzhai (NZ), Beizhai (BZ), and Danaozi (DN) (Fig. 1). [Results] We obtained 1 042 independent effective photographs from 9 359 camera-trapping days, including 865 photos for mammals and 177 photos for birds. We identified 43 species, including 19 mammal species from 11 families in five Orders and 24 bird species from 14 families in three Orders. The highest relative abundance index measured as detected rate was the Red Panda (Ailurus fulgens, 3.25), followed by Tufted Deer (Elaphodus cephalophus, 2.77) and Blood Pheasant (Ithaginis cruentus, 1.02). As to seasonal change in species richness, it was low in winter, high in autumn and summer, with the highest in August. The activity intensity of these alpine species had also noticeable seasonal and months changes, with differences among species. Beta diversity comparison revealed that birds and mammals showing different spatial distribution patterns between the middle and south section of the Gaoligong Mountains, the turnover components were higher than nested ones for birds while the mammals showing the opposite pattern. [Conclusion] Our study provided detailed records of ground-living bird and mammal species in alpine habitats in the southern section of the Gaoligong Mountains. There were significant seasonal variations in avian and mammalian species richness in the alpine ecosystem, which may be related to vertical migration along altitude gradients and seasonal change of food resources. According to these results, we suggested that altitudinal movement and seasonal variations in animal activity intensity need to be considered in managing the alpine ecosystem, and all alpine ecosystems in the Gaoligong Mountains should be protected.