This study examined postoperative speech function in ten patients who underwent mesopharyngeal resection and reconstruction using radial forearm flap. Patient age ranged from 49 to 71 years (mean 60 years) with 9 males and 1 female. Speech function was assessed by articulatory and velopharyngeal function. Articulatory function was judged by intelligibility of monosyllables and sentences. The percentage of 100 Japanese monosyllables perceived as correct in each case were scored. Intelligibility of sentences was evaluated using the Hirose standard. Velopharyngeal function was fiberoptically examined both in soft-blowing and at rest, and visual information about velopharyngeal closure was obtained. Correlation between the extent of resection and the speech function was then analysed. In order to maintain over 50% speech intelligibility and an excellent state in the Hirose standard, the extent of resection in the soft palate is particularly important. This result has to be explained in correlation with the resected range of the levator muscle, which is important for velopharyngeal closure. Surgically treated mesopharyngeal cancer patients face several functional problems. In order to counsel patients more meaningfully before surgical intervention, information about the postoperative speech function should be made available. The goal of reconstruction is to achieve acceptable speech in order to maintain the patients' quality of life. The results in this study reveal that resection which doesn't extend to the opposit side of the soft palate, can achieve the goal by utilization of the foream flap, because its pliable nature brings out the residual function of the levator.