Sulcus vocalis refers to a condition in which a furrow occurs along the upper medial edge of the vocal folds. The etiology of sulcus is controversial. Bouchayer et al. proposed that sulcus vocalis is congenital and there are what appeared to be transition forms bet-ly. If the resulting opening is as large as the cyst, the resulting empty pocket becomes a glottic sulcus. In addition, mucosal invagination may proceed on the upper and lower margins of the cyst and then sulcus vocalis can be formed. We experienced 3 cases of epider-moid cyst associated with sulcus vocalis on the upper and lower margins of the cyst and thought that presenting them would be help-ful to understand the pathogenesis of the sulcus vocalis from the epidermoid cyst.