Objectives: Vocal fold polyps can be treated with either surgical resection or conservative therapy based on voice therapy. This study was designed to analyze the success rate of voice therapy and identify factors that are predictive of the response to this treatment for vocal fold polyps. Methods: This was a retrospective cohort study of 92 consecutive patients who were diagnosed with vocal fold polyp(s) and received voice therapy. We divided the patients into responding and non-responding groups. We analyzed clinical and voice parameters related to the voice results. Results: After voice therapy, 40 patients showed improved findings and did not undergo surgical treatment. By univariate analysis, female patients (54.9%) and small polyps (56.1%) showed a good response to voice therapy. In multivariate analysis, female sex (odds ratio [OR] = 0.34; confidence interval [CI]: 0.14–0.81, P = 0.01) and small size (OR = 0.15; CI: 0.05–0.47, P < 0.01) were significantly related to a successful voice response. In small polyps, the sessile type of polyp was found to be related to a good response rate (OR = 0.24; CI: 0.11–0.95, P = 0.04). Conclusions: Voice therapy is more effective for small vocal polyps, particularly the sessile type, in female patients.