The purpose of this study is to compare the effects of intraoperative fixation and postoperative rehabili-tation on postoperative results in arthroscopic PCL reconstruction. We analyzed the posterior stability of the knee on 47 patients(48 knees) with posterior cruciate liga-ment injury whose posterior cruciate ligament had been recostructed arthroscopically and followed for minimum 1 year period at Asan Medical Center from March 1993 to May 1998. The patients were divided into the two groups according to intraoperative fixation and postoperative rehabilitation. In A group, one interference screw or staple fixed in distal femur and proximal tibia irre-spective to bone quality and fixation strength during screw insertion, and rehabilitation was started as early as anterior cruciate ligament reconstruction. In B group, additional screw or staple was fixed if fixa-tion strength was weak during screw insertion, and delayed rehabilitation program was performed as schedule. Lysohm knee score was 65.3 in group A and 75.8 in group B preoperatively but 86.0 in group A and 86.5 in group B at last follow up postoperatively. posterior stability was determined by difference in pos-terior tibial translation between the injured and the opposite knee with Telos device. Differences in poste-rior tibial translation on average were 6.9 and 3.0 mmin group A and B, respectively. Conclusively, arthroscopic posterior cruciate reconstruction with firm fixation strength and delayed rehabilitation program is effective to restore more reliable posterior stability.