The purpose of this study was to understand the relationship between executive functions and mathematical abilities to determine the contribution of these functions to math performance. In this study, 30 students were selected from among 4th graders of elementary school, in two groups with low achievement in mathematics (poor) and high achievement in mathematics (strong), such that their IQ and reading ability were as close as possible. These groups were measured and compared in terms of attention by means of continuous performance test and shifting by means of Wisconsin Card Sorting Test. The ANOVA and t-test showed that the low-achieving group stood significantly lower than the high-achieving group in shifting, which mirrors the effect of this function in math performance of the students. However, there was no significant difference between the two groups in terms of attention.