Objective To understand the participation of medical students' extracurricular physical exercises and explore the relationship between medical students' extracurricular physical exercises and their physical self-esteem, so as to provide references for physical training of students and physical education in colleges. Methods Questionnaire survey was used. In November 2020, totally 291 medical undergraduates enrolled from 2018 to 2020 in a college in Beijing were selected as the research objects and their extracurricular physical exercise, physical self-esteem were evaluated through physical activity rating scale-3 and physical self-perception profile. The survey data were analyzed by t-test, ANOVA, nonparametric rank sum test and spearman correlation analysis. Results The scores of male students in exercise volume[24.00(28.00) vs. 12.00(18.00)], physical self-esteem [(66.79±15.08) vs. (62.56±17.55)] were significantly higher than those of female students(all P<0.05). The total physical self-esteem scores of medical students who exercise with high volume (77.69±21.62) and medium volume (70.82±14.30) were significantly higher than those of small exercise volume (59.66±14.32) (all P<0.01). The correlation coefficients between the volume of extracurricular physical exercise of medical students and the dimensions of physical self-esteem were physical self-worth (r_s=0.292), sport competence (r_s=0.382), and physical condition (r_s=0.427), attractive body (r_s=0.270), physical fitness (r_s=0.334)(all P<0.001). Conclusions Male students and medical students whose extracurricular physical exercise is moderate or above have higher levels of physical self-esteem. The volume of exercise is positively correlated with the level of physical self-esteem of medical students. Medical students should increase the volume of exercise so as to increase the level of physical self-esteem.