PURPOSE. The purpose of this study was to compare men with women in terms of speech intelligibility, to investigate the validity of objective acoustic parameters related with speech intelligibility, and to try to set up the standard data for the future study in various field in prosthodontics. MATERIALS AND METHODS. Twenty men and women were served as subjects in the present study. After recording of sample sounds, speech intelligibility tests by three speech pathologists and acoustic analyses were performed. Comparison of the speech intelligibility test scores and acoustic parameters such as fundamental frequency, fundamental frequency range, formant frequency, formant ranges, vowel working space area, and vowel dispersion were done between men and women. In addition, the correlations between the speech intelligibility values and acoustic variables were analyzed. RESULTS. Women showed significantly higher speech intelligibility scores than men and there were significant difference between men and women in most of acoustic parameters used in the present study. However, the correlations between the speech intelligibility scores and acoustic parameters were low. CONCLUSION. Speech intelligibility test and acoustic parameters used in the present study were effective in differentiating male voice from female voice and their values might be used in the future studies related patients involved with maxillofacial prosthodontics. However, further studies are needed on the correlation between speech intelligibility tests and objective acoustic parameters.