Objectives : This study was performed to investigate the association of social support with burden in mothers with handicapped preschool children. Methods : The study subjects were 95 mothers who had handicapped children, and the data were collected from September 29 to October 11, 2003 using the self-administerd questionnaire which was composed the several characteristics, social support and burden of mothers. The used statistic methods were t-test, analysis of variance(ANOVA), Pearson's correlation analysis and multiple regression analysis. Results : The mean and standard deviation of burden was 71.60±14.82, and that of social support was 22.45±7.24. The related factors with burden of mothers were mother's age, monthly income, happiness level of family and children with developmental disability. The number of family and social support were negative correlation and age at diagnosis was positive correlation with burden of mothers(p＜0.05). As a result of multiple regression analysis, the social support was statistically significant related factor with burden of mothers with handicapped preschool children. Conclusions : It was demonstrated that social support, an important factor relating to burden imposed on mothers of children with disabilities, can be considered as an intervening variable which can contribute to decrease of the burden.