This study examined the predictive role of child cognitive, social, emotional, and behavioral dimensions assessed at the age of 4 ½, as well as of academic school readiness before the entry to primary school, on mathematics achievement at the end of Year 1. A sample of 58 children and their parents participated in this longitudinal study. Initial correlations indicated significant associations between child intelligence quotient (IQ), inhibitory control, set-shifting, dysregulation profile, academic school readiness, and their subsequent performance in mathematics. A hierarchical regression analysis showed that inhibitory control at 4 ½ years significantly predicted mathematics achievement at the end of Year 1 over and above the effect of academic school readiness before entering primary school. These results add to the existing literature by highlighting the impact of child executive functioning assessed during the preschool years on subsequent mathematics performance in early school years.