Objective: To investigate the impact of physical self-efficacy on physical activity and physical health among university students, so as to provide insights into formulation of the strategy to improve physical activity and physical health among university students. Methods: Freshmen and sophomores were sampled from a university in Guangzhou City using a convenience sampling method from December 2021 to April 2022. Students' demographics and types of sport exercises were collected using questionnaire surveys. Physical self-efficacy was tested using the Physical Self-efficacy Scale, and physical activity was measured using the International Physical Activity Questionnaire-Short, while physical health was evaluated using the school physical health standard test. The associations of physical self-efficacy with physical activity and physical health were examined using a multivariable logistic regression model. Results: Totally 4 171 questionnaires were allocated, and 3 811 valid questionnaires were recovered, with a effective recovery rate of 91.37%. The respondents included 1 582 males (41.51%) and 2 229 females (58.49%), and included 1 967 freshmen (51.61%) and 1 844 sophomores (48.39%). The median score of physical self-efficacy was 36 (interquartile range, 7) points, and there were 1 777 students reaching the national standard of physical activity (46.63%) and 1 112 students with excellent and good physical health (29.18%). Multivariable logistic regression analysis showed that physical self-efficacy was a promoting factor for the proportion of reaching the national standard of physical activity (OR=1.054, 95%CI: 1.043-1.064) and excellent and good physical health (OR=1.109, 95%CI: 1.096-1.122) after adjustment for gender, grade, specialty and source of students. Conclusion The improvement of physical self-efficacy may increase the proportion of reaching the national standard of physical activity and excellent and good physical health among university students.