One hundred and eleven children, 50 boys and 61 girls, form three third grade classes were rated for aggressive behavior by their classmates. Concurrently, the mothers of all subjects were interviewed individually to obtain information about their child rearing attitudes and practices. Relations between child rearing variables and aggressive scores of subjects were evaluated by correlation with the following results: 　　1. With increased maternal punishment for aggression at home, there is increased aggressive behavior of children both in school and at home. 　　2. Maternal rejection seems to be an important factor of instigation at home to heighten the aggressive behavior of children both in school and at home. Maternal shame on children is another instigative factor. However, the relation is held only for girls' aggressive score at home. No significant correlations and are found between maternal restrictivenless, lack of nurturance parental disharmony and agressive behavior of children. 　　3. Mother's own aggressive behavior is not signifcantly related to the child's aggressive behavior in school or at home as well as the child's sex-role identification. Besides, the child's internalization of parental standards seems not to be an important inhibitive factor to suppress the aggressive behavior of children. 　　4. Children of higher socio-economic status show less aggressive behavior than children of lower socio-economic status. 　　5. Maternal child rearing attitudes and practices have much more effects on the aggressive behavior of girls than that of boys. 　　6. Maternal authoritarian attitude toward children has nothing to do with their children's aggressive behavior. However, mothers with democratic attitude have less aggressive girls in school, but same relationship is not held for boys. Mothers who show more marital conflicts and refuse their home making roles have more aggressive children at home. 　　7. There is a high negative correlation between the child's aggressive score and his social status in the class.