The information about node location of wireless sensor network plays an important role to the application of network, however, it’s limited of sensor network resources, therefore, this paper puts forward a kind of effective defense method to the wormhole attack of DV-Hop, which is directed to the short comings of that the safety performance of DV-Hop algorithm poor, and the location process easily attacked by the destructive worm hole and so on. The method is that introducing EPWDV-Hop algorithm which is an effective detection defense algorithm against the wormhole attack into the DV-Hop algorithm. According to the simulation test of Matlab software, it shows that the modified algorithm can not only improve the precision of location, but also is very good to prevent the wormhole attack in algorithm.