In order to improve the voltage stability margin of power system, the network reconfiguration is proposed based on fuzzy clustering. The network accident (such as a tie line short circuited or overload) or other network failures occurred due to uncertainty should be removed quickly. It needs other lines replace the fault point to avoid interrupting the power supply. But there are a variety of candidate solutions at this moment. This paper proposes a fuzzy clustering method to classify many candidate branches, and selects the most candidate branch on the basis of improving voltage stability margin at a maximum to complete the network reconfiguration. The proposed method is tested in IEEE 30-bus system to show its feasibility and validity. This work is supported by Natural Science Research Foundation of Jiangsu Universities (No. 14KJB470003 and No. 16KJB470004).