Comparing All-Inside endoscopic technique and conventional techniques for posterior cruciate ligament(PCL) reconstruction, To study the feasibility, advantages and disadvantages of All Inside endoscopic technique reconstruction of PCL. Methods These were 74 patients who were reconstructed the PCL referred to our department of orthopaedic from July 2016 to July 2021. Among them, 43 cases were in the conventional group, was 31 cases in the All-Inside endoscopic group. In the conventional group, allogeneic tendons were used as grafts, femoral and tibial tunnels were established from the outside to the inside, and the ligament was fixed with extrusion screws. In the All-Inside endoscopic group, Femoral and tibial tunnels were made from the inside to outside by All-Inside endoscopic technique and the ligament was fixed with Adjustable loop titanium plate (TightRope)（Arthrex，USA）.Results 74 patients who were treated with surgery were followed up 2 ~ 6 years. All preoperative symptoms got better apparently in the last follow-up, such as the pain of the knee, swelling and limitation of range of motion. The posterior drawer test (-), the back Lachman test(-), IKDC classification, Lysholm scores after reconstruction were significantly increased when compared with that prior to surgery . In the All-Inside endoscopic group, the knee IKDC score: 27 patients were rated normal（87.1%）, 3 patients were rated nearly normal（9.7%）, 1 patients were rated abnormal（3.2%）. The rates of the normal and nearly normal were 96.8%. The knee function Lysholm scores: before operation(51.7±4.3 points), after operation(92.2±3.6 points),remarkable increased, the difference have statistical significance （t=24.43, P=0.001）. In the conventional group,the knee IKDC score: 31 patients were rated normal（72.1%）, 9 patients were rated nearly normal（20.9%）, 3 patients were rated abnormal（7%）. The rates of the normal and nearly normal were 93.0%. The knee function Lysholm scores: before operation(52.4±7.3 points), after operation(90.2±4.7 points),remarkable increased, the difference have statistical significance（t=21.56, P=0.001）. Conclusions The application of All-Inside endoscopic technique to reconstruct the PCL injury can reach or exceed the conventional technique to reconstruct PCL, and can effectively restore the stability of the knee joint.