This study investigated the relationships between socio-economic status of family, home environment stimulation, children’s behavioral problems, and interactive peer play of preschool children. Surveys of 2,150 Korean mothers with their preschool children(Mean age= 51.9 months) from the Panel Study of Korean Children by Korea Institute of Child Care and Education were analyzed using structural equation modeling. Each variable's confirmatory factor analysis showed the correlation coefficient below .85, which made a satisfactory level of discriminant validity. The model fit to the data well, with an agreeable level of index. The major findings were as follows. First, SES did not significantly affected children’s interactive peer play. Second, SES significantly affected home environment stimulation and children’s behavioral problems. And the relationship between SES and children’s behavioral problems are significantly mediated by home environment stimulation. Third, the relationship between SES and children’s interactive peer play are significantly mediated by home environment stimulation and children’s behavioral problems. These results help better understand the paths among the home characteristics and children’s behavioral problems on children's social development. Interpretation and implication of the results have been discussed.