Research Findings: In Study 1, we observed 32 Chinese kindergarteners playing a number board game with their caregivers in dyads. Number board game playing provided important opportunities for kindergarteners and their caregivers to talk about an array of number concepts, but their numeracy-related exchanges rarely went beyond counting. In Study 2, 88 Chinese kindergarteners and their parents were randomly assigned to 1 of 4 groups, namely, the game with parent training group, the game without parent training group, the exercise book group, and the control group. After a 4-week intervention, kindergarteners in the 3 treatment groups who began as relatively unskilled in numeracy showed comparable improvement in 3 numeracy tasks, and the effect sizes were often larger in the game with parent training group than in the game without parent training group. Moreover, kindergarteners in the 2 game groups tended to show relatively heightened mathematics interest. Practice or Policy: Findings of these 2 studies suggest that number board game playing has the potential benefit of promoting kindergarteners' numeracy competence and mathematics interest. Training of parents might even optimize kindergarten children's gains from parent-child number board game playing.