This paper is concerned with the cardiac sound measurement and analysis system for in-home use of heart abnormality monitoring. The heart sound acquiring system is consisted of a traditional chest-piece, earphone, microph- one, IC recorder. The recorded data is transmitted to a computer by USB interface for analysis based on cardiac sound characteristic waveform method (CSCW), which is extracted from an analytical model of single degree-of-freedom(SDOF). Furthermore, the characteristic parameters (T1, T2, T11, T12) are defined by the time intervals between the crossed points of the CSCW and a threshold value (THV), which are related to the first sound and the second sound and are used for discriminating normal and abnormal heart sounds. Also, an easy-understanding graphical representation for these parameters is considered, so that, even for an inexperienced user he or she is able to monitor his or her pathology progress easily. Finally, a case study on the abnormal/normal cardiac sounds is demonstrated to validate the usefulness and efficiency of this proposed system and the cardiac sound characteristic waveform method.