To discuss the factors associated with intra-abdominal and pelvic adhesion of women with scar uterus after cesarean section of prepregnancy. Methods: The clinical data of 120 women with scar uterus after cesarean section of prepregnancy from January 2016 to January 2020 were collected retrospectively. The intra-abdominal and pelvic adhesions was graded based on the exploration during cesarean section. The correlation between the time interval in two cesarean sections, the times of abortion between the two cesarean sections, the times of curettage after abortion between the two cesarean sections, the degree of orifice of uterus opening, or the amniotic fluid pollution of the women and their intra-abdominal and pelvic adhesion was analyzed. Results: Among 120 women, 61 women (50.8%)in study group were found different degrees of intra-abdominal and pelvic pelvic adhesion during cesarean section, and other women without intra-abdominal and pelvic pelvic adhesion were in control group. The incidence of intra-abdominal and pelvic adhesion (65.6%)of the women with the interval of the two cesarean sections ≤2 years was significantly higher than that (34.4%)of the women with the interval of the two cesarean sections >2 years. The greater the opening degree of orifice of the uterus in the previous cesarean section, the higher the incidence of intra-abdominal and pelvic pelvic adhesion. The incidence of intra-abdominal and pelvic adhesion of the women with Ⅱ-Ⅲ amniotic fluid pollution was significantly than that of the women with Ⅰamniotic fluid pollution or without amniotic fluid pollution. The lower the level of hospital for previous cesarean section, the higher incidence of intra-abdominal and pelvic adhesion. The incidence of intra-abdominal and pelvic adhesion (33.3%)of the women in the study group was significantly higher than that (10.2%)of the women in the control group (all P＜0.05). Conclusion: The opening degree of orifice of the uterus, the degree of amniotic fluid pollution, the interval between the two cesarean sections, the hospital level for previous cesarean section, and the complications after previous cesarean section of the women are all the relevant factors of their intra-abdominal and pelvic adhesions occurrence.