The invention discloses a singing sound synthesis system, which comprises a storage unit, a beat unit, an input unit and a processing unit, wherein the storage unit is used for storing at least one melody; the beat unit is used for indicating a beat; the input unit is used for receiving a plurality of sound signals; and the processing unit is used for processing the sound signals and generating asynthesized singing sound signal. The sound signals are generated by reading aloud or humming by a user according to the melody and the beat, so each sound signal corresponds to the melody and the beat and is processed directly, and the time and the cost of pre-recording a large number of user corpuses are saved, the system resources are saved, and the song synthesis speed is improved; furthermore, the finally obtained synthesized singing sound has tones of users, and the effect is quite lifelike.