Partial knee ankylosis is a recognized complication following open operative procedure, trauma and disease processes about the knee. It can result from the formation of intraarticular adhesion and contracture of the capsule as well as the shortening or adhesion of the quadriceps mechanism. Physical therspy and occasionally manipulation under the anesthesia may improve the results, but performed late, these methods will be useless. This is a review of 30 patients who had severe limitation of motion in the knee joint following open operative procedures or trauma about the knee and who were treated by the percutaneous release of adhesions under the arthroscopic control. The following results were obtained; There were 17 males and 13 females, and the age of release ranged from 23 to 69 years old (av. 42.8years old). The interval between arthroscopic adhesiolysis and the last follow-up evaluation ranged from 6 months to 5 years and 7 months(av. 23 months). The interval between the last open operative procedure or trauma and arthroscopic adhesiolysis ranged from 3 months to 4 years(av. 15 months). The average preoperative knee ROM was 38.8°the postoperative ROM was 121.1°and the average final knee ROM at follow-up was 102.6°So the average loss of ROM was 18.5°The arthroscopic adhesiolysis seems to be applied to the various conditions of the partial knee ankylosis and the results are better than the other surgical procedures when it was performed early enough.