The CO₂ laser has been widely used in otorhinolaryngology surgery, especially in the laryngology field. The effect of CO₂ laser to tissue is not only vaporization of fluid in the tissue instantly but also ignition and scattering of the solid element by the pressure difference resulting from vaporization. The CO₂ laser surgery has many benefits which are precision, extraordinary hemostatic effect, maximal operative field and easier instrumentation, minimal postoperative edema and scarring. All of these factors make the CO₂ laser a useful therapeutic tool for the treatment of laryngeal lesions. We performed the CO₂ laser surgery to treat 180 cases of various laryngeal lesions during a period of Mar. 1985 through Aug. 1990. And the following results were obtained ; 1) Sex ratio was 1.2 : 1, being 98 cases of male and 82 cases of female. Age distributions showed the highest incidence in 4th decade(68 cases, 37.8%), and then 5th decade(48 cases, 26.7%), 3th decade(34 cases, 18.8%) in order. 2) Chief complaint of all patients was hoarseness, and associated symptoms with hoarsness were sore throat. dyspnea, foreign body sensation, dysphonia, coughing and sputum. 3) Distribution of disease in order of frequency were vocal polyp 84 cases(46.6%), vocal nodule 59 cases(32.8%), Reinke's edema 19 cases(10.5%), intubation granuloma 5 cases(2.8%), papilloma 4 cases(2.2%), hemangioma 3 cases(1.7%), others 6 cases(3.4%). 4) Patient's own subjective evaluation of voice result after operation showed ; 68 cases(37.8%) had markedly improved results, 98 cases(54.4%) had moderately improved results. But 11 cases(6.1%) had unchanged results, 3 cases(1.7%) had worse results. And so 166 cases(92.2%) had improved results. 5) Postoperative laryngeal examination in the 166 cases of improved results revealed a free field of any lesion. And the examination in the 14 cases(7.8%) of unresponsed results revealed that remnants of lesion were observed in 4 cases(2.2%), recurrence of lesion in 6 cases(3.4%), glottic defect in 4 cases(2.2%). 6) The complications of CO₂ laser surgery had been reported in other surveys. In our study, the complications occurred in 15 cases(8.3%) among 180 cases. But no troublesome complications were observed. 7) Finally, the results of the present study suggested that the application of CO₂ laser in therapy of various laryngeal diseases was established as a safe and beneficial procedure.