Background and Objectives : A voice therapy can be used the basic method for the voice improvement of patients with the voice disorders. However, according to each voice disorders, various results of treatments have been reported. The purpose of this study was to evaluate the clinical features of the patients who did not improved after the voice therapy and to explore factors that could affect the results of the voice therapy. Material and Method : There are patients (n=49) diagnosed as the vocal nodule and patients (n=13) diagnosed as the vocal polyp. They received the voice therapy more than 6 times from September, 2000 to August, 2001. Clinical features, stroboscopic findings, esophagographic findings and PNS x-ray findings were compared between the improved and the nonimproved groups. Results : Before the voice therapy, PNS x-ray found two of all patients had the paranasal sinusitis. 14 of the vocal nodule patients (28.6%) and 8 of the vocal polyp (61.5%) had GERD in the esophagogram. However, the recovery rate after the voice therapy had no significant difference in both the vocal nodule and vocal polyp with GERD. In patients with the vocal nodule, 47 of 49 (95.9%) improved after the voice therapy. 6 of them were found the clearly decreased lesion in the stroboscopy. But, in patients with the vocal polyp, 7 of 13 (53.8%) improved after the voice therapy and did not have improvement through the stroboscopy. Conclusion : If the treatment of GERD is given with the voice therapy after the evaluation of GERD, it is helpful to increase the effects of the voice therapy. And, if patients were improved partially or unimproved after voice therapy, it was important to evaluate all factors-motivation, compliance and cooperation-related with patients will. Through this, some factors might be minimized except diseases differences.