This paper proposes a behavior observation method for plateau pika (Ochotona curzoniae) in degraded alpine meadow in the Source Zone of the Yellow River (SZYR) on the Qinghai–Tibet Plateau based on continuous monitoring videos to observe its activity rhythm. The video surveillance cameras are installed facing toward degraded alpine meadow in the SZYR and run from March 2021 to February 2022 to record time allocation of plateau pika behavior (i.e., digging, foraging, guarding, moving and other behaviors) and its daily, monthly, and seasonal activity rhythm. The results indicate that: (1) The most active ground activity time is between 10:00 and 16:00, meanwhile it is inactive at night, which proves it plateau pika is diurnal animals. (2) Digging and foraging are frequently occurring behaviors among its daily activities, which occurs from 9:00 to 12:00 and 16:00. (3) Compare to other season, winter sees relatively frequent occurrences of digging and foraging according to the seasonal analysis results. (4) From annual perspective, digging and foraging accounted for 66.13% of plateau pika activity, while guarding accounted for 13.35%, moving accounted for 11.64%, and other behaviors accounted for 8.88%. There is a significant difference in the frequency of each behavior between the two groups (P < 0.05). The behavior observation method using video surveillance camera contributes to behavioral ecology information of plateau pika.