Abstract: From July 2017 to June 2018, the infrared camera was uesd to continuously monitor the wild Sichuan Takin (Budorcas tibetanus) in Tangjiahe National Nature Reserve and analyze its activity rhythm. During the study period, a total of 16,840 effective camera working days and 62 camera sites of the distribution of Sichuan Takin were recorded and a total of 1455 independent and effective records were obtained (267 in spring, 158 in summer, 823 in autumn and 207 in winter). The kernel density estimation and coefficient of overlap were used to analyze the daily activity rhythm of Sichuan Takin. The results showed that: (1) There were two activity peaks in the daily activity rhythm of Sichuan Takin in different seasons (spring: 06:50—09:10, 14:50—19:50; summer: 06:50—08:00, 14:50—20:10; autumn: 07:10—10:00, 15:30—19:00; winter: 08:50—09:40,14:40—19:50), and all distributed in the morning and evening. (2) The peak activity of Sichuan Takin in the morning was autumn (2.83 h) > spring (2.33 h) > summer (1.67 h) > winter (0.83 h), while the peak activity in the evening was summer (5.33 h) > winter (5.17 h) > spring (5 h) > autumn (3.5 h). (3) There were seasonal changes in the activity rhythm of Sichuan Takin, among which there were significant differences between spring and autumn, spring and summer, and summer and autumn (P<0.05), while there were no significant differences among other seasons. The overlap index was highest in spring and summer (Δ=0.922), and lowest in autumn and winter (Δ=0.829). The activity of Sichuan Takin was diurnal, mainly in the daytime with only a few activity traces at night.