Laboratory mice are well known to use ultrasonic sounds in social communication. We established new vocalizer mutant (sng mutant), which emitted human audible sounds in both sexes. The human-audible-range vocalization was started after sex-maturation and ceased in old ages. The sounds consisted of a rapid series of syllables at 4-11 syllables per second, each syllable 5-100 ms long, in the 2-15 kHz band (https://www.youtube.com/watch?v=yLu37VvCozw). The syllables held a variety of waveforms and the characteristics of frequently used waveforms within the syllables differed between individuals and according to context. Our detailed sound analysis revealed that the human audible vocalization emitted by sng mutants depended on different sound production mechanism from ultrasonic vocalization usually used in laboratory mice. The playback experiment using 3 kinds of sounds (the human-audible vocalization, a noise and artificial sounds) showed that the sng mouse vocalization elicited more approach behavior in wild type females than the two other sounds, indicating that the vocalization had some relation to the social interaction. In addition, auditory deprivation of sng mutant resulted in immature development of their vocalization. We observed increases of c-fos gene expression in several regions of sng mutant brain by in situ hybridization experiment. These results suggested that sng mutant exhibited new vocalization behavior equipped with unique characteristic never seen in usual laboratory mice. Our established vocalization model opens the possibility of new studying neural functions controlling vocalization behavior in mice.