Arithmetic word problems are particularly difficult to solve when they are presented in inconsistent language, where the keyword (e.g. "more than") does not match with the correct arithmetic operation (e.g. subtraction). To solve these problems, one should abstain from deriving the arithmetic operation directly from the keyword (keyword heuristic). Using a negative priming task, this study examined the need of inhibiting the keyword heuristic among 9- to 10-year-olds and compared the inhibition efficiency of children with differential problem-solving abilities. Results showed a negative priming effect, suggesting that the keyword heuristic had been inhibited when solving the inconsistent-language problem. Importantly, there was no difference in inhibition efficiency between the above-average and below-average problem solvers. Hence, at least for elementary-grade children, what differentiates their problem-solving abilities may not be related with their efficiency in inhibiting a misleading heuristic.