A clinical analysis was performed on 110 patients(200 sides) of chronic paranasal sinusitis, who underwent surgical treatment at the Dept. of Otorhinolaryngology, Hallym University Medical College from April to September, 1990. The following results were obtained : 1) Patients group consisted of 79 males and 31 females. The average age of the group was 30 and 57% among them was less than 30 years old. 2) Nasal obstruction(76%) was the most frequent chief complaint and nasal polyp(57%) was the most frequent rhinologic finding. 3) The most frequent pneumatization of frontal and sphenoid sinuses were well pneumatized(56%) and sellar type(78%), separately. In Caldwell's view, the average area of frontal sinus was 4.15cm² and, in Waters' view, the average area of maxillary sinus was 7.99cm². Radiological findings of maxillary sinus were total haziness(33.2%), mucosal thickening(32.3%) partial haziness(26.8%) in order. Those of anterior ethmoid sinus wer severe mucosal change(53.2%), mild mucosal change(38.2%) and normal finding(8.6%) and those of posterior ethmoid were severe change(48.2%), mild change(40.5%) and normal finding(11.4%). Haziness of frontal sinus was observed in 31.8% and sphenoid sinus revealed mucosal thickening(31.8%) and haziness(22.7%). 4) In puncture of maxillary sinus via inferior meatus, the status of natural ostium were patent(46.2%), stenotic(46.2%) and obstructed(7.6%) and the characteristics of antral content were purulent(39.1%), mucoid(33.3%) and clear(27.6%). Bacterial culture of antral content(during P & I) showed no growth(47.6%), α-hemolytic Streptococcus(14.3%) and Staphylococcus aureus(9.5%) in order and those of antral content(by C-L operation) showed no growth(45.1%), α-hemolytic Streptococcus(15.7%), coagulase positive Staphylococcus(11.8%) and Staphylococcus aureus(9.8%) in order. 5) In four cases, only Caldwell-Luc's operation was done and in the other cases, various intranasal procedures were combined. 6) Intraoperative examination showed that mucosal thickening(39.1%) was predominant in maxillary sinus and huge polyp(53.7%) was in anterior ethmoid sinus and severe mucosal disease(38.5%) was in posterior ethmoid sinus. Those of frontal sinus were normal(38.8%), severe disease(35.5%) and mild disease(22.7%) in order and those of sphenoid sinus were normal(22.7%), mucosal disease(2.9%) and empyema(1.0%), excluding the 72.5% of unchecked cases, where we could not exactly located the sphenoid. 7) Histopathological examination of maxillary antral mucosa showed that fibrous(28.9%), mixed(23.5%) and infiltrative type(19.3%) were in order. 8) The duration of illness was significantly longer in the patient with chief complaint of nasal obstruction than in the patient with hyposmia. And it was also longer in the case with histopathologically fibrous type than in the case of infiltrative or mixed type(p<0.05). 9) The cases of obstructed natural ostium, in puncture and irrigation of maxillary antrum, were more related to the empyema than the other intraoperative findings. And the case with antral content of pus were more related to the mucosal thickening or the empyema than the others. 10) Radiological findings were well correlated to the intraoperative finding but the size of the maxillary or frontal sinus were not correlated to the severity of disease in the intraoperative examination.