Objective To study the treatment efficiency and function recovery of posterior cruciate ligament tibial avulsion fractures under arthroscopic with figure-of-eight suture fixation. Methods From March 2019 to March 2021 ,a retrospective analysis was conducted on 28 adults patients with posterior cruciate ligament tibial avulsion fracture who were treated with "8" suture in the "4" position by three-portal under arthroscopy. The average follow-up period was 19 months，ranging from 12 to 24 months．The follow-up assessment included posterior drawer test，Anti-Lachman test、Lysholm、IKDC knees core and the radiological evaluation．Results All 28 cases successfully achieved reduction and bone union．The knee function was good．The results of posterior drawer test，Anti-Lachman test were negative．Preoperative Lysholm score was 33.14±9.60, postoperative Lysholm score of knee joint was 84.07±5.43, the difference was statistically significant (P<0.05); Preoperative IKDC score was 32.39±84.79, and postoperative IKDC score was 84.79±4.42, the difference was statistically significant (P<0.05). Conclusion The arthroscopic figure-of-eight fixation in “4” position for posterior cruciate ligament tibial avulsion fractures using suture subminimal invasive 、 convenient with satisfactory reduction and fixation，which can benefit the postoperative rehabilitation．It can achieve excellent results．