Abstract :[Objective] To compare the clinical effects between posterolateral approach and extended modified posteromedial approach in the treatment of posterior pilon fracture. [Methods] 67 patients with posterior Pilon fracture were treated with buttress plate fixation from January 2015 to December 2018, including 35 cases of posterolateral approach and 32 cases of extended modified posteromedial approach. The operation time, blood loss, excellent and good reduction rate, fracture healing time, AOFAS ankle and hindfoot score and VAS score were compared between the two groups. [Results] The patients in both groups completed the operation successfully and there were no serious complications during the operation. All patients were followed up for more than 12 months. No fracture nonunion, failure of internal fixation and ankle stiffness were found during follow-up. The operation time, blood loss, excellent and good reduction rate and AOFAS score in the extended modified posteromedial approach group were significantly better than those in the posterolateral approach group (P < 0.05),but there was no significant difference in fracture healing time and VAS score between the two groups（P >0.05）.[Conclusion] Compared with the posterolateral approach, extended modified posteromedial approach can provide a good range of operative field. Direct reduction, fixation and evaluation of reduction effect for posterior pilon fracture can reduce operation time, blood loss, firm fixation combined with supporting plate, and allow early ankle function rehabilitation exercise, which can obtain more satisfactory clinical results.