Abstract: The purpose of the conceptual integration theory is to reveal the cognitive mechanism behind language meaning generation, which is in overcoming shortfalls of conceptual metaphor theory, which run up in the generic space, two input space and space for synthesis. People went through the combination of the concept of cognitive activities such as combination, diffusion and expansion when they understand and integrate the meaning of metaphor. In addition, the existing knowledge background also plays a very important role in understanding metaphorical meaning.