The high cases of aggressive behavior in the Indonesian primary school indicate the low empathy of children. One of the factors that influence empathy development is the social environment. Furthermore, Indonesian society is very diverse as the social environment of children. Therefore, this study aim was to see the relationship between diversity and child's empathy. Several previous studies provided evidence of a correlation between diversity and prejudice. Some studies also proposed that prejudice attitude of children and parent predicts each other. Additionally, prior researches proved the correlation between prejudice and empathy. Therefore, this study also intended to investigate the mediating role of parent's prejudice attitude on the relationship between diversity and child's empathy. Participants of this research were 233 pairs of parent and child in Jakarta. We measured the variables using the adapted Kids' Empathy Development Scale, the adaptation of blatant prejudice scale, and the scale of opportunities for contact. This study showed that the direct effect of diversity on children empathy was not statistically significant, but the parent's prejudice attitude confirmed to mediate the relationship. Our findings indicate that diversity does not directly affect children's empathy, but diversity influences the parents' prejudice attitude which then affects the children's empathy.