PURPOSE: to describe the vocal acoustic characteristics of emission in vocal fry of male adult patients, with surgically repaired post-foramen cleft. METHODS: study of cases involving four male subjects with surgically repaired post-foramen cleft. Acoustic analysis concerning sustained emission of vowel [a] was accomplished in modal register and vocal fry, through the programs Multi Dimensional Voice Program (glottic source analysis) and Real-Time Spectrogram (spectrographic analysis), both by Kay Elemetrics Corp. RESULTS: through the vocal fry spectrography analysis we perceived: decrease of definition, intensity and definition band spectrography in some formants, decrease of intensity as for the entire spectrum, and a slight decrease of noise in high frequencies; damping effect showed slight increase. Through the glottic source analysis in vocal fry, we perceived: fundamental frequency in the modal speech register zone and it was higher when compared to the emission for comparison in the modal register; large increase in the measures that show variation of frequency and amplitude; most of the jitter and shimmer measures were significantly increased; increased measures of noise, voice break, unvoiced segment and vocal tremor; and soft phonation index (SPI) significantly decreased. CONCLUSIONS: the findings evidence the high instability and the emission noise in fry register, as well as its weak intensity and diminished transglottic air flow.