Partial knee ankylosis is a recognized complication of following open operative procedure, trauma and disease processes about the knee. Intraarticular trauma or surgical procedures such as TKR, synovectomy or patellar fracture were main source of intraarticular or extraarticular soft tissue adhesion and contracture were resulted from distal femoral and proximal tibial fractures. The purpose of this study is to report the value of arthroscopic adhesiolysis of partial knee ankylosis and to evaluate the clinical results of its application in various conditions. From October 1982 to December 1992, 56 cases in 54 patients who had severe limitation of motion in the knee joint following open operative procedure or trauma about the knee were treated by fibroarthrolysis under the arthroscopic control. For release of thick fibrous tissue, we used our designed blunt metal bar. The following results were obtained. There were 30 males and 24 females and the age at the time of release ranged from 20 to 69 years old(average 38.7 years old). The interval between last open operative procedure or trauma and arthroscopic adhesiolysis ranged from 3 months to 6 years(average 16 months). The interval between arthroscopic adhesionlyssis and the last follow up evaluation ranged from 1 year to 9 years(average 49 months), The average preoperative range of knee motion was 42.2 and the postoperative range of motion under the anesthesia was 115.5 and the average final knee range of motion at follow up was 101.3. So the average loss of motion between postoperative and final motion was 14.2. Complications were one case of patellar and tibial condylar fracture respectively. In the author's experience, arthroscopic adhesiolysis seems to be applied to the various condition of the partial knee ankylosis and the results are better than the other surgical procedures when it was performed early enough16).