In order to cut down the localization accuracy problem of wireless sensor network (WSN), a novel node localization method is proposed with back propagation neural network (BPNN). At first, the calculation of node localization is presented by ranging interval and signal strength, and the parameters are rapid solving base on BPNN. Finally, a simulation experiment is conducted to study the influence key factor with NS2 and MATLAB. The results show that, compared other localization algorithm, this method has good suitability, and it could effectively reduce the localization error.