This study examined the effects of parent attachment on children’s happiness. The study sample was 1019 elementary school fourth graders (528 boys, 491 girls) who had participated in the twentieth wave of the Panel Study on Korean Children (PSKC). The data were analyzed using Pearson’s correlations and regression analysis with SPSS 23.0. The results are as follows. First, paternal attachment and maternal attachment had a significant correlation with children’s happiness. Second, paternal trust, maternal communication, maternal isolation, and paternal isolation are predicted variables for children’s happiness. These results add to a better understanding of the mechanism linking paternal attachment and maternal attachment to children’s happiness. These findings can serve as an important contribution to future research and practices for increasing children’s happiness.