the authors evaluated diagnostic value of non-invasive methods and other modalities in diagnosing primary lymphedema. We also evaluated the radiologic findings. Dirent(N=7) and indirect lymphangiograms(N=7) CT scan(N=4) and ultrasonogram(N=3) were performed on 14 patients with primary lymphedema of the lower extremities. Also comparison CT scan and ultrasconogram were performed on 50 normal volunteers. The results were as follows: 1. Lymphedma was classified as praecox and tarda according to the onset age of symptoms. Their percentages were 71.4 % and 28.6% respectively. 2. lymphangiogram classification showed the following in the order of frequency; hypoplasia(78.6%) aplasia(14.3%) and hyperplasia(7.1%) 3. The mean midtibial subcutaneous fat ratio of the lymphedema patients was 37.73% on the CT scan which was greater than that of the normal subjects(20.05$pm$14.04%) 4.On the ultrasonogram mean premidtibial dermis and subcutaneous fat thickness of the lymphedema patients was 6.3mm which was greater than that of the normal subjects (2.9$pm$2.4mm) 5. Inconclusion CT scan and ultrasonographic examination were helpful as a non-invasive method for evaluating the follow-up of patients treated for lymphedema.