Abstract: The method of identifying tank target using wavelet theory has been studied in this paper. It is known that, in time domain,the millimeter wave (MMW) radiation feature of tank target is similar to its main interferences (e.g.,metal waste and possible water surface),so it is hard to distinguish them. To solve this problem,a wavelet decomposition method has been adopted to extract the energy information from millimeter-wave signals at different scales. On the basis of general energy component and detail centralizing characteristic energy level,a corresponding identifying threshold has been worked out using statistical method. Theoretical analysis and the results of simulation show that this method is feasible and effective.