Vocal process granuloma can occur commonly by laryngopharyngeal reflux (LPR), vocal abuse or misuse. It has been reported that voice therapy is employed with medication therapy for the patients who has vocal process granuloma, however research about effect of voice therapy can be hardly founded. For that matter, the primary aim of this study was to evaluate the effect of therapeutic method we implement. Thirty one patients who has been diagnosed with vocal process granuloma from January, 2007 to June, 2009 participated in this study. 19 patients among them are provided voice therapy and medication, 12 patients take only medication. Voice therapy is implemented ranging from 5 to 19 sessions (mean: 8.6 sessions). We provided explanation about problem each patient has, voice rest, SKMVTT$^{(R)}$, abdominal breathing, and relaxation in session. All subjects were examined by videostroboscopy, perceptual assessment, acoustic and aerodynamic measures. Consequantly, the greater part of the patients (78.9%) who is treated by voice therapy and medication are confirmed disappearance or decrease of granuloma, it shows better results compared with the group provided only medication (66.7%). Especially, the period of drug administration is 3.7 months in the group runs parallel with voice therapy, the period of other group is 7.8 months. The results of acoustic and aerodynamic measures after treating indicates there are significant decrease in Jitter, Shimmer, and NHR, and increase in MPT, Psub (p<.05). However, there is no large difference statistically even though voice quality has improved since the therapy. In conclusion, it is verified that the voice therapy to the vocal process granuloma patients taking medication is effectual method, we recommend combining voice therapy with medication when treatment is needed for the vocal process granuloma patients.