The structure is one of the important elements that influence architectural design. The structural design of the contemporary architecture has broken through the structural support in traditional ideas. Now, the designers attach more and more importance to the expression of structural form. The structural exPression has become one of the important form design methods during architectural creation. The structural expression focuses on the structural artistic elements and the bonds between structure and art in order to turn the abstract structural ideas to the vivid architectural language. This article discusses the concept and the meaning, the base and the soul of the structural expression. It suggests that the unity between technique and art is the main content of structural expression. On this foundation the basic principles and some design methods of structural expression were summarized. It is hoped that the designers pay more attention to the concept and bring some new thoughts on the concept.