In order to improve the performance of the wavelet analysis in the process of the heart sound signals, in this paper, we construct a wavelet basis which is exclusively used for processing the heart sound signals on the basis of wavelet theory construction. Firstly, we propose a general method of constructing a compactly supported biorthogonal wavelet which has even length filter banks, Secondly, according to the characteristics of heart sound signals, we discuss the structure principle of heart sound wavelet and a synthesis model of heart sound signals based on the heart sound wavelets. Finally, we construct the heart sound wavelet on the basis. In order to highlight the advanced nature and practical application of heart sound wavelet in processing heart sound signals, the theory and numerical simulation of heart sound wavelet are analyzed more comprehensively. Experimental results show that compared with commonly using the db and bior series wavelets, using the heart sound wavelet to process the heart sound signals can obtain good denoising effect, accurate classified information about heart sound and low reconstruction error rate. So the heart sound wavelet provides a new method of deep studying of heart sound feature extraction and identification and has a positive significance in describing the details of the individual characteristics of the heart sounds. The paper designs a method of the special wavelet which is based on the application object, which provides a new approach to the selection of wavelet basis in engineering applications.