Objective  To explore the influence of muscle and fat distribution on sit-up ability of female college students.   Methods  A total of 1560 female students majoring in non-physical education in a Guangxi University were randomly selected. Body composition was measured by the bioresistance antibody component meter. According to the National Physical Health Test Standard, the height, weight and sit-ups of female college students were measured. The students were divided into four groups according to the score of sit-ups:<60 points,60-69 points,70-79 points, ≥80 points. SPSS 22.0 statistical software was used to analyze the data.    Results  There were statistically significant differences in body fat rate, total fat mass, trunk fat mass, trunk fat rate, visceral fat area, visceral fat mass and subcutaneous fat mass in different sit-ups (F value were 3.414, 2.914, 2.881, 3.347, 3.064, 3.235, 2.766,  P<0.05). That was, the fat parameters in the 60-69 group were the highest and ≥80 the lowest. However, there was no significant difference between total muscle mass and trunk muscle mass in each score segment. After correcting for age, height, and weight factors, except for visceral fat area and visceral fat mass, the correlation between other fat parameters and sit-up score were negatively correlated, which were statistically significant (r<0, P<0.05). There was a positive correlation between each muscle parameter and sit-up performance (r>0, P<0.05). Compared with other parameters, the correlation coefficient between trunk muscle mass and sit-ups was the largest.    Conclusion  The distribution of fat and muscle has different effects on sit-up ability. Female college students’sit-up ability is greatly affected by subcutaneous fat and trunk muscle, and has nothing to do with visceral fat.