Objective To study the anatomic reconstruction method of posterolateral complex (PLC) in combination injury of posterior cruciate ligament (PCL) and PLC of knee, and explore its early clinical effect. Methods A total of 16 patients (10 males and 6 females) with PCL and PLC injuries admitted to the Affiliated Hospital of Southwest Medical University between January 2017 and January 2019 were retrospectively analyzed. The PCL was reconstructed with artificial ligament under arthroscopy, and autologous semitendinosus and gracilis muscles were used to reconstruct the PLC using the modified Laprade procedure. We measured the tibia posterior displacement on stress radiographs, lateral compartment gapping on varus stress radiographs, external rotation angle of tibia, and range of motion (ROM) of knee before and after operation, observed and recorded the postoperative complications, and evaluated the joint function according to the score of International Knee Documentation Committee (IKDC) and Lysholm Knee score before and after operation. Results All the 16 patients were followed up for 12 to 25 months, with an average of 17 months. The stress radiographs at the last follow-up showed that the tibia posterior displacement [(18.42±4.93) vs. (3.63±2.37) mm], lateral compartment gapping [(13.70±3.19) vs. (3.28±1.89) mm], external tibial rotation at 30° and 90° of flexion [30°: (14.75±2.84) vs. (2.44±2.06)°; 90°: (15.94±2.52) vs. (2.72±2.14)°] were significantly reduced compared with those before surgery. Lysholm score (45.42±10.94 vs. 85.19±7.11) and IKDC grade were obviously improved compared with those before surgery. All the above indicators showed statistically significant differences (P<0.05). The postoperative ROMs of knees of 13 patients returned to normal, and 0-10° flexural function was limited in 3 patients. None of the patients suffered from infection, loose internal fixation, nerve injury, or other complications. Conclusion Modified Laprade PLC reconstruction combined with arthroscopic reconstruction of PCL can effectively restore the posterior and posterolateral rotatory stability of the knee, and is worthy of clinical promotion.