The study aimed to study the inhibitory mechanism in syllogistic reasoning when the outputs of the heuristic strategy and analytic reasoning disagree. We manipulated the congruency of the quantifier of the conclusion with those of the two premises according to the matching strategy and the validity of the syllogism. After each syllogistic evaluation task, a lexical decision task was used to check if the semantic content of the conclusions was inhibited. The results suggested that after correctly solved conflict problems (match-invalid or mismatch-valid), the semantic priming effect of the words related to the two terms in the conclusion diminished. For no-conflict problems, the recognition time of the related words was faster than that of the unrelated words. The results suggested that inhibition on the content of a syllogism may not only be triggered by the conflict induced by the believability but also by the surface structure of the syllogisms.