In order to improve maintenance of weight reduction, a long-term (5 month) weight reduction class for obese women consisting of repeated group learning three times a month in areas of dietary regimen and practice of physical exercise, and self-help group activities was conducted at a health center. Maintenance of achieved weight reduction was studied six months and one year after completion of the class. The results are as follows. 1) Among 30 alumni, percentages of rebound, regaining weight of more than half of reduction during the class, were 18% at six months and 48% at one year after the class. These results appear to indicate the difficulty in maintaining weight loss. 2) However, when changes were studied in terms of fat mass and lean body mass, rebound of fat mass, regaining fat mass of more than half of reduction, was very small--only 5%, through the follow-up periods--while lean body mass increased gradually. These results indicate very good maintenance of fat mass reduction, and from the view point of the objective of weight reduction which is principally fat mass reduction, this objective was supported. 3) The attendees were divided into two groups, diet group and exercise group. There were almost no differences in the follow-up results for weight maintenance between the two groups. This can be attributed to the fact that since the combination of dieting and exercise was emphasized in both groups, with moderate energy restriction and balanced food intake in the dietary regimen and aerobic walking for exercise in addition to the classroom learning, instructions for lifestyle changes were rather similar for both groups.