One hundred sixty-five Hong Kong Chinese children were administered measures of early mathematics, visual-spatial skills, and executive functioning (working memory, inhibition, shifting, updating) once in kindergarten (mean age = 62.80 months, SD = 3.74) and again in first grade (mean age = 77.25 months, SD = 4.60). In kindergarten, visual-spatial skills, inhibition, shifting, and working memory were all uniquely associated with concurrent mathematics performance; in first grade, only working memory and visual-spatial skills were significantly related to concurrent mathematics abilities. Furthermore, working memory and visual-spatial skills in kindergarten predicted 19% of the variance in children's mathematics performance in first grade, beyond the autoregressive effects of mathematics performance in kindergarten as well as demographic variables. Findings highlight the importance of working memory and visual-spatial skills for young Chinese children in mastering mathematics.