Objective:To investigate the expression and significance of integrin α5β1 and heparanase (HPA) in placental site trophoblastic tumor (PSTT) and choriocarcinoma tissue. Methods:Western blot was used to detect the integrin α5β1 and HPA protein expression in 20 cases choriocarcinoma tissue, 15 cases PSTT tissue and 40 cases normal villi. Results:The integrin α5β1 and HPA protein expression in choriocarcinoma tissue were obviously higher than PSTT tissue and normal villi (P<0.05); The integrin α5β1 and HPA protein expression in PSTT tissue were obviously higher than normal villi (P<0.05). Conclusions:Abnormal expression of integrin α5β1 and HPA maybe closely related to the development of choriocarcinoma and PSTT.