Backgrounds and Objectives : There have been reported many studies which evaluate the effectiveness of combined laryngomicrosurgery(LMS) and voice therapy for the patients with benign vocal cord lesions. But the difference of voice improvement by onset time of voice therapy has not been reported. The purpose of this study is to analyze the differences of voice improvement by voice analysis test between the two groups with different onset time of voice therapy. Materials and Methods : Two groups, each of which comprises 15 patients, were analyzed. For the one group, the voice therapy was initiated 1 day after LMS. For the other, the therapy was initiated 1 week after LMS. Voice analytic parameters of the two groups were statistically analized to identify difference in voice improvement. Results : All measured parameters improved after voice therapy in two groups and showed no significant difference between two groups. Conclusions : The onset time of voice therapy after LMS has no significant impact on post-operative voice quality in the patients with benign vocal cord lesions. Early onset of post-operative voice therapy may serve as treatment modality for patients with benign vocal cord lesions.