Hidrocystoma belongs to benign tumors of sweat glands. It varies in size from a few millimeters to 1,5cm in rare cases. We report an atypical case of giant hidrocystoma of the eyelid. A 27-year-old woman consulted for a gradually progressing tumor of the right upper eyelid, with ptosis. The tumor was excised, and the histopathological exam revealed a giant hidrocystoma. The originality of this case lies in its atypical size and functional complications in a young patient.