The aim of this study was to examine whether highly math-anxious (HMA) individuals show a deficit in behavioral inhibition when performing tasks with numerical stimuli. Event-related brain potentials were recorded while 28 HMA and 28 low math-anxious (LMA) individuals performed two Go/NoGo tasks. In the numerical task, single-digit numbers were presented and participants were asked to press a button if the number was even. In the non-numerical task, letters were presented and the button had to be pressed if the letter was a vowel. Groups did not differ in response time for the Go trials and responses were slower in the numerical than in the non-numerical task. As for hit rate, more errors were committed in NoGo than in Go trials for both groups in both tasks. Importantly, the Go minus NoGo difference in hit rate was larger in the numerical than in the non-numerical task only for the HMA group; i.e., it was harder for this group to withhold pressing the button in NoGo trials in the numerical task. As for brain response, Nogo-N2 and Nogo-P3 were observed in both tasks for both groups; importantly, Nogo-N2 was larger for the LMA than for the HMA group only in the numerical task. Group differences were also found in the N2d in the numerical task. These results suggest that HMA individuals might have a domain-specific deficit in the response inhibition in numerical tasks, what could contribute to their low mathematics achievement.