Mucocele is a benign, chronic, expansile and cyst-like lesion of the paranasal sinuses which contains sterile, mucoid secretions. The mucoceles are most frepuently found in the frontal sinus. Obliteration of the frontal sinus and nasofrontal duct, with removal of all mucosa, seems to prevent mucocele formation and is accepted standard at this time. Authors experienced a case of huge frontoethmoidal mucocele with frontal bone defect. We used osteoplastic flap technique through the bicoronal approach to remove the mucocele and the defect was obliterated with cancellous bone & galeo-frontalis flap. The postoperative results was good.