Abstract: Studies on verbal humor have been made from various perspectives, among which co gnitive mechanism is drawing more and more attention. Based on the classical Inc ongruity Theory, this paper combines modern Semiotics and Conceptual Blending Th eory, and puts forward a new cognitive-semiotic model for cognitive op eration mechanism involved in verbal humor comprehension. In verbal humor compre hension, the recipient interprets the same key concept (signifier) into two diff erent signifieds which are mapped by each other and projected into the blend spa ce. If and only if the recipient perceives the incongruity between the two signi fieds, humor effect can be produced. This paper is not only helpful to the enric hment humor study but also a tentative research from the perspective of Cognitiv e Semiotics.