Abstract: Mental space theory (MST) addresses linguistic phenomena mainly from the perspective of the information carried by the utterance itself.The roles played by language users in the construction of mental spaces, however, are ignored to a certain extent.Linguistic adaptation theory (LAT), which focuses on the choice made by both the speaker and the hearer during the negotiation and adaptation process of communication, can make up this defect in MST.Therefore, by combining the two theories, the paper attempts to present the operational mechanism of strategic verbal impoliteness (SVI), a special linguistic phenomenon employing impoliteness to perform other illocutionary acts than being impolite.It is pointed out that in producing such a speech act, adaptation is made by the speaker not only to the context, but also to his preset mental space building plan.Without any explicit space-builder, the strategic impolite utterance induces the hearer to construct mistakenly the content of a fictive space into a reality space, and thus achieves its strategic effect.