Mucoceles are secreting cysts lined with sinus mucous membrane and enlarged by accumulation of the products of secretion and desquamation. Mucoceles of frontal sinus develop following blockage of the nasofrontal duct due to chronic infection, trauma, or surgery of the frontal sinus. We have recently experienced two cases of frontoethmoidal mucoceles with complications. The osteoplastic frontoethmoidectomy with abdominal fat obliteration, and the external frontoethmoidectomy were done respetively.