Objective To evaluate acoustic effects of laryngeal microsurgery on vocal polyp, vocal cyst and vocal leuko- plakia. Methods 300 cases in vocal fold diseases were measured acoustically pre - and post - microsurgery. Results After openation, jitter, shimmer and NNE decreased statistically in vocal polyp and vocal cyst patients, and did not improve in vocal leukoplakia patients. Whether or not the surgery was done, F0 of all patients did not change Conclusion Laryngeal microsurgery had definite effect on clearing benign focus. After surgery, vocal functioin improved in vocal polyp and cyst patients, and in vocal leukoplakia, there was no improvement in such a short time as one week.