This article first reviews the main points of conceptual metaphor theory proposed by Lokoff & Johnson and blending theory by Fauconnnier. Through the comparison, it gives us a clear comprehersion of the similarities and differences between these two theories, and then comes to the condusion that they are complementary concerning the explanation of metaphor. Finally, it analyzes the problems in the two theories, which paves the way for the development and refinement of conceptual metaphor theory and blending theory.