Abstract: Audio signal recognition is of great practical value in music database retrieval technology and computer automatic music composing.Taking the piano scale signals as an example,this paper focuses on the analysis,matching and identification of the collected audio signals in frequency domain,so as to realize the recognition of the audio signals.Firstly,the spectra of standard music notes are obtained by using the Goertzel algorithm,and the obtained sequence energy is normalized to standard template.Secondly,the spectrum of the audio signal to be identified is calculated and matched with the template of each standard sound.Finally,the sound notes are found by the best matching results.Through the test of the piano standard audio file,the mobile piano playing software and the real piano performance recording,the method has high recognition accuracy and good anti-noise performance.