The authors has performed double contrast arthrography of knee in 96 cases at Busan National University Hospital for about 4 years from May 1976 to April 1980. The 31 cases of them were analyzed both clinically and raiolgraphycally with the background of definite diagnosis confirmed by operation. The results are as follows. 1. Of the 31 cases, 25 cases were male (80.6%), and 6 cases were female(19.4%), Male exceeded female in ratio of 5 : 1. 2. 22 cases(70.1%) were distributed form 15 to 26 years of age. 3. The left knee joint was a more prevalent site, The ratio of left to right was 16 : 14. One case was bilateral. 4. In 17 cases(45.2%) of the 31 cases, there was a positive history of trauma, 14 cases had no specific history(54.8%). 5. The operative findings showed lateral meniscus lesion in 25 cases(80.6%) : medical meniscus lesion in 2 cases (6.5%) : discoid meniscus in 2 cases(6.5%) : lateral mensectomy in 1 cases (3.2%) : and lateral meniscus lesion with medial collateral ligament tearing in 1 cases (3.2%). 6. In 25 cases of the 31 cases, the radiologic abnormal findings corresponded to the operative finding . 5 case revealed somewhat different features with the operative findings. One case which showed no abnormal roentagenograhic findings was found to have abnormality at operation. As a result, the diagnostic accuracy of arthrography was 96.8%.