Abstract: Wavelet neural network has it’s fatal defect “dimension disaster” for fault diagnosis in analog circuit.According to the multiresolution analysis thought in the multiwavelet space,a multiwavelet neural network model is obtained.Some compact support,symmetric and orthonormal multi-scale functions and multiwavelets are adopted as the activation functions in the model.Simulation results indicate that the multiwavelet neural network converges more rapidly than wavelet neural network,and avoids the “dimension disaster”.Experimental results support the result of theoretical analysis.