Abstract: Similarity evaluation results of ship radiated noise signals could be one of evidences for the applications such as source recognition of measured noises and the confidence computation of simulated noises. A similarity evaluation method of ship radiated noise signals is presented in this paper. The auditory, continuous spectrum, line spectrum and DEMON spectrum features are synthesized. And for each feature, its concrete properties used for evaluation and the corresponding similarity computation method are investigated and selected carefully. The total similarity evaluation value of two ship radiated noise signals is then calculated based on the similarity values of those four features. Numerical experiments are conducted with real measured ship radiated noise signals. The experiment procedures of similarity evaluation and experimental data analysis are provided in detail. Experimental results show that, the similarity values evaluated with the method coincide with the real similarity of measured ship radiated noise signals, and the evaluated similarity value ranges are easy to distinguish. Thus the evaluation results of the method are of high confidence.