Abstract: The application of conventional neural network in analog circuit fault diagnosis might lead to false diagnosis.A wavelet neural network is proposed according to multiresolution analysis theory.Firstly,constructing tensor product scaling function and tensor product wavelet function according to the theory of tensor product;then the tensor product scaling function and wavelet are adopted as the activation functions for wavelet network.The proposed wavelet neural network is applied in analog circuit fault diagnosis.Experimental results show that this wavelet neural network can exactly diagnose those faults which have been trained.Furthermore,it can classify new faults exactly.Therefore,it can avoid the problem of false diagnosis.