An electromagnetic wave discrimination device according to the present invention discriminates electromagnetic waves, and includes an acquisition section, a feature quantity calculation section, a similarity calculation section, a classification section, a discrimination section, an output section, and a storage section. The acquisition section receives communication signals of a predetermined frequency, and samples waveform data of the communication signals every predetermined time to obtain sample data for each predetermined time. The feature quantity calculation section calculates amplitude feature quantities for each predetermined time, based on the sampling data for each predetermined time. The similarity calculation section calculates degrees of similarity with respect to the amplitude feature quantities for each predetermined time. The classification section classifies the communication signals for each predetermined time into clusters to obtain cluster analysis results of the communication signals for each predetermined time, based on the degrees of similarity. The discrimination section discriminates communication signals constituting one cluster for each of the clusters to obtain discrimination results, based on the cluster analysis results of the communication signals for each predetermined time. The output section outputs the discrimination results. The storage section stores the amplitude feature quantities, the degrees of similarity, the cluster analysis results, and the discrimination results.