Objective Clinical diagnosis and treatment of uterine scar pregnancy stage classification after cesarean section Methods From January 2017 to December 2019, clinical data of 133 patients with CSP were retrospectively analyzed. CSP was divided into two stages according to pregnancy time and size of pregnancy cyst: early stage and late stage; CSP was classified into type I, type II and type III according to the thickness of myometrium at uterine scar, location of gestational sac and growth direction of gestational sac. The stages and types were scored by CSP: early stage: 1 point for type I, 2 points for type II, and 3 points for type III;Late stage: 2 points for type I, 3 points for type II, and 4 points for type III;Finally, CSP was divided into light type, ordinary type and severe type according to CSP staging and type scoring method, and the corresponding treatment plan was further selected. Results Score 1: 20 light patients were selected ultrasound-guided uterine aspiration. Score 2-3: 108 ordinary type patients were pretreated with oral mifepristone before ultrasound-guided uterine aspiration; Score 4: 5 cases of severe patients were directly selected for surgical treatment. Conclusion A total of 133 patients with CSP were divided into light type, ordinary type and severe type by stage classification CSP score. Three different clinical treatment schemes were selected respectively, all of which achieved safe, accurate and effective treatment results.