In the context of promoting cultural self-confidence and self-improvement in the new era, the extension innovative method is applied to the redesign of national patterns in order to preserve the national patterns, make the traditional national patterns revitalized in the new era, and improve the efficiency of the national pattern redesign. An extension design method for the redesign of national patterns is proposed, which characterizes the explicit information such as morphological features and the implicit information such as semantic description of pattern primitives through primitive theory and extension analysis method, and establishes a pattern primitive library for pattern information storage, and generates a sufficient amount of creative design solutions at one time in the design practice stage by using the extension transformation method. Finally, the Zhuang brocade patterns are taken as examples to realize the application of creative patterns with national characteristics and good meanings on modern clothing, verifying that this method can provide an idea for the protection and inheritance of national patterns and help to promote the development of modern creative design practice for traditional culture.