Hydatid cyst (echinococcosis) is an infectious disease caused mainly by Echinococcus granulosus, a parasite transmitted by dogs and encountered first in the liver and then in the lungs. Involvement in the head and neck region is uncommon, and pterygopalatine fossa disease resulting from hydatid cyst is extremely rare, with only 4 reported patients. In this report, the authors present a patient with exophthalmus caused by a primary hydatid cyst and involving the pterygopalatine fossa which treated only with endoscopic endonasal approach.