Pneumosinus dilatans is a rare condition of paranasal sinus, which is most commonly found in males of the age between 20 to 40. That is defined hypersinus as the enlargement of a paranasal sinus beyond the upper limits of normal. The deformity is caused by an abnormal enlargement of the paranasal sinus by hyperpneumatization. A valve mechanism raising the pressure inside the sinus is regarded to be responsible for this condition. A preoperative computed tomography scan is used to illustrate the anatomical condition and possible etiologic mechanisms and the most commonly affected sinus is the frontal sinus. 
Numerous methods have been suggested to repair the anatomical deformities of frontal sinus and we represent a method of correction for pneumosinus dilatans, too. We approached the frontal sinus by using a bicoronal incision and exposed total frontal sinus to remove total outer wall at one piece. We remodeled outer wall of fontal sinus by one piece and fixed with absorbable plates and screws. Ten months after the successful operation, the patient was satisfied with a good cosmetic result without recurrence. The latest, this comsmetic surgery is attractive and we wanted to improve frontal sinus bossing commonly, but it is not usual. Here, we present a case of pneumosinus dilatans of the frontal sinus of the repair method.