Reconstructive surgeries for old ligament injuries of the knee vary according to the site and nature of injury as well as the age, health, physical demand and cartilage condition of the patients. No single best procedure is present for any old ligament injuries, but the most adaptable technique should be applied according to accurate diagnosis and experiences of surgeon. We reviewed our experiences of several reconstructive surgeries for the 38 cases with chronic ligamentous instabilities and summarized as following. 1) The most prevalent age of the patients was the third decades and males were 5.3 times more common than females. 2) Traffic accidents was the most common cause. 3) Tear of anterior cruciate ligament and medial collateral ligament appeared to be the most common injury. 4) Results at final follow up was not seemed to be affected by severity or location of ligament injury. 5) Intraarticular reconstruction without combined extraarticular reconstruction was not considered to be effective enough for anterior cruciate ligament deficient knee. 6) Although the number of cases was not large enough, we reviewed various reconstructive surgical techniques for comparison and evaluated the effects.