Hydatid disease has a high incidence in the countries of the temperate zones such as Turkey. Only few cases in the head and neck region have been reported in the literature. Our case, an unusual localization of hydatidosis, i.e. hydatid disease of the infratemporal fossa of a 9-year-old male patient suffering from a swelling of the left maxillary region which was diagnosed by CT, is presented. The lesion visualized on CT images was compressing the neighbouring structures. The possible diagnosis was made based on the images obtained from CT examination.