The designation "keratocyst" was used to describe any jaw cyst in which keratin was formed to a large extent. A rare incidence of bilateral mandibular cysts (odontogenic keratocysts) was related to third molar teeth. Herein, we report two cases of bilateral keratocystic odontogenic tumor in a 22-year-old male and 15-year-old female, which was diagnosed by a series of investigations and treated appropriately.