Objective To investigate the relationship between body self-cognition and weight losing behavior of college students.Method 200 colleges students（100male

100female;100medical students

100non-medical students）in Chengdu were surveyed by self-edited questionaire and the survey results were analyzed.Results The number of male students with correct body self-cognition was 48

accounting for 48.0%;that of female students was 51

accounting for 51.0%;and the difference in correct self-cognition between the two genders was not statistically significant（χ2=0.18

P=0.66）.The number of medical students with correct body self-cognition was 46

accounting for 46.0%;that of non-medical students is 53

accounting for 53.0%;the difference between different majors was not statistically significant（χ2=0.98

P=0.32）.The number of students with correct body self-cognition and weight losing behavior was 36

accounting for 36.4%;the number of students with wrong body self-cognition and weight losing behavior was 52

accounting for 51.5%;the former was lower than the latter and the difference was statistically significant（χ2=4.64

P=0.04）.The number of male students with weight losing behavior was 32

accounting for 32.0%;that of female students was 56

accounting for 56.0%;the difference in weight losing behavior between two genders was statistically significant（χ2=11.69

P=0.00）.The number of medical students with weight losing behavior was 40

accounting for 40.0%;that of non-medical students was 48

accounting for 48.0%;the difference in weight losing behavior between different majors was not statistically significant（χ2=1.30

P=0.25）.Conclusion Colleges must attach great importance to body self-cognitive bias of students and they need to strengthen college students′education of correct self-cognition and help students to establish a correct attitude of their body to promote the sound development of their body and mind.