Our retrospective study of 5 cases of sinus mucocele confirmed its rarity and occurrence at any age. This uncommon disease might be due to an association of inflammation, ostium closure and hypersecretion. The volume of the fronto-ethmoidal mucocele let us operate on patients either by orbito-superciliary route or through the frontal scalp. Functional endoscopic surgery, presently suggested for mucocele treatment, was not used because of our lack of experience in this surgical method.