Difficulties in reading and math are more likely to occur simultaneously than difficulties in either area alone; however, the research on that comorbidity is relatively sparse. The purpose of this study was to examine the relation between early reading skills as predictors of math achievement. A group of 102 kindergarten and 65 first-grade students were assessed with curriculum-based measures of early reading and early math, and a measure of broad math achievement. The results of multiple regression analyses indicated that when early numeracy was controlled for, the measures of early reading did not explain unique variance in math achievement among students. Interestingly, screening with only measures of early reading skills yielded acceptable area under the curve (AUC) values but did not yield accurate identification of students at risk for math difficulties (MD) when misclassification and specificity were taken into account. Results suggest that early math measures are most accurate in identifying students at risk for MD in early grades. Findings provide further insight into the relation between math and reading skills at the start of formal schooling. Authors provide recommendations for a combination of reading and math screeners to predict broad math achievement.