The purpose of this study is to develop the weight control program for the psychiatric inpatients gained their weight on atypical antipsychotics. It was adopted and the effect of its nursing intervention was measured. The subjects of this study were 10 inpatients of experimental group and 15 inpatients of control group at Y University Medical Center in Daegu . The data were collected from May 1, 2000 to April 25, 2001 and analyzed by descriptive statistics. Wilcoxon Rank-Sum test and Mannwhitney test using SPSS/PC+ (10.0) program. This weight control program which consists of diet therapy, exercise, and behavior modification was educated to experimental group in advance. The effect of weight control program were measured by weight change every week. The results were as follows: Hypothesis I such as "The experimental group received weight control program will loose or retain weight at least" was supported(Z=-2.820, P=.005). Hypothesis Ⅱ such as"The controll group who did not receive weight control program will gain the weight" was supported(Z=-3.299, p=.001). From the above results, it was concluded that weight control program would be used as effective nursing intervention for weight gained inpatients on atypical antipsychotics. It would also a contribute to preventing recurrence by improving compliance of long-term neuroleptic medication.