The clinical study of 183 cases of laryngeal mass was observed and 88 cases of vocal nodule and polyp, 18 cases of laryngeal papilloma and 25 cases of laryngeal cancer are confirmed histopathologically and the following results of microscopic examination were obtained. I. The clinical study of laryngeal mass. 1) Among total cases of 183, vocal nodule is 82 (45%), vocal polyp 53 (29%), postintubation granuloma 3 (1%), laryngeal papilloma 18 (10%), tuberculosis 2 (1%), cancer 25 (14%). 2) The sex ratio of male to female is 3 : 4 in vocal nodule, 27 : 26 in vocal polyp, 1 : 2 in postintubation granuloma, 3 : 2 in laryngeal papilloma, 11 : 1 in cancer. 3) The age distribution is fourth and third decade in vocal nodule, fifth and fourth decade in vocal polyp, third decade in postintubation granuloma, second and fifth decade in laryngeal tuberculosis, seventh and sixth decade in cancer. 4) The distribution of symptoms is 5 month-1 year in vocal nodule and polyp, less than 1 year in laryngeal papilloma and postintubation granuloma, 1-3 year in laryngeal tuberculosis and cancer. 5) The location of the mass is between the anterior 1/3 and middle 1/3 of vocal cord in vocal nodule, vocal polyp and papilloma, middle 1/3 and posterior 1/3 in postintubation granuloma and arytenoid in laryngeal tuberculosis, and glottic (55%), supraglottic (32%), subglottic (16%) in laryngeal cancer. 6) The side of the lesion is bilateral in vocal nodule and papilloma, and the ratio of right to left is 5 : 3 in vocal polyp, 2 : 1 in postintubation granuloma. 7) The size is 1-2 mm (67%) in vocal nodule, 3-5mm (42%) in vocal polyp, 6-10mm (67%) in postintubation granuloma, 1-2mm (39%) in laryngeal papilloma, more than 10mm in tuberculosis and cancer. 8) Among the symptoms, the hoarseness is in more than 90% of disease entity, the sore throat in tuberculosis and cancer, the dyspnea in postintubation granuloma, papilloma, tuberculosis and cancer. 9) In the past history, certain relationship with smoking is noted in cancer (40%) and tuberculosis (50%), and the history of frequent URI attack is in papilloma (33%). 10) In occupation, certain statistical significance was not noted. II. The histopathological study. 1) Most polyp and nodules were covered with stratified squamous epithelium, but focal hyperkeratosis (32%), parakeratosis (9%), acanthosis (24%), atrophy (19%) were rather frequently oserved. Hyperkeratosis and acanthosis was most frequently seen. 2) The histopathologic findings were divided respectively into fibrous stage (15%), myxoid stage (50%), vascular stage (21%), hyaline stage (18%), according to W.H.O classification. 3) The histopathologic findings of 18 cases of laryngeal papilloma were squamous and exophytic type in 17 cases (94.5%), and transitional and inverted type in 1 case (5.5%). 4) In 25 cases of laryngeal cencer, the ratio of squamous to adenocarcinoma was 24 : 1.