A 47 year old Korean came to our clinic, on April-4-1959, having the history of frontal protrusion, headache and Rt. exophthalmus for the past 7 years. E.N.T. examination and X-ray study of the frontal sinus revealed frontal ethmoidal sinus mucocele, which had destroyed the neighboring bony structures with regular outline. External surgery was performed on the frontal sinus region, at that time a brown chocolatelike semifluid was evacuated from the sinus. An attempt was made to remove the entire mucosa, and a rubber tube was inserted through a newly created naso-frontal duct. The post-operative progress was satisfactory without complications, the rubber tube was removed 6 weeks following surgery. On the discussion, we would like to emphasize some of the problems of this procedure. First, the cosmetic problem produced over frontal region by the surgery. Second, the removal of the entire mucosa and ethmoidal cells. Third, a permanent naso-frontal opening, which narrowing is probably most important as a cause of failure of this procedure.