Abstract To analyzes the characteristics, problems and enlightenment of physical activity observation tools, so as to provide reference for researchers to quickly and accurately choose appropriate observation tools to evaluate children s and adolescents physical activity. Literature search is conducted in eight databases of Chinese and English, including CNKI, Wanfang, VIP, Web of Science, PubMed, Medline, ERIC, and SPORTDiscus. Ultimately, eight observation tools for assessing physical activity in children and adolescents are included. Through summarization and comparison, it is found that the applications of those tools cover multiple age groups, the observation indicators cover multiple dimensions for each with varying emphases, and the applicable contexts vary in their specific background information, and recording methods tend to be quantitative. However, several issues remain to be addressed in practical applications. First, the observation indicators need to be supplemented and improved; second, physical activity in community environments and academic classrooms requires further attention; third, physical activity intensity needs to be scientifically evaluated; fourth, observation and recording methods need to be integrated and innovated; fifth, the number of observation subjects needs to be expanded. Future research could focus on developing observation tools tailored to the characteristics of Chinese children and adolescents, while drawing on foreign observation tools to comprehensively assess physical activity among children and adolescents.