Gate is one of the building elements and has important function in the system of Chinese classical buildings. For one thing, the gate has turned from a building component into a single structure, and becomes the key part of space construction in the traditional courtyard buildings; for the another, the gate has not only practical and commemorative function, but also shows off the rigorous hierarchy, and becomes the symbol of the confucian feudal ethic. Through the analysis of their function, form and symbol, memorial meaning as well as the component relationship between gate and plan, gate and elevation, we can show up its profound connotation of social ethics and architectural aesthetics, and offer reference to architectural creation.