Background: Nasal polyposis is a common problem facing the otolaryngologist. Its incidence is estimated to be in the range of 0.2 to 4.3%. It may be associated with other conditions such as bronchial asthma (about 25%-30% of polyposis patients) and Aspirin sensitivity (12%). Objectives: The aim of this work was to study the importance of searching and identifying the effect of medical versus surgical modalities in treatment of chronic allergic nasal polyps. Patients and Methods: Thirty patients with bilateral nasal polyps were enrolled in this study. They were randomly arranged into 2 groups. Group I was treated by functional endoscopic sinus surgery while Group II was treated by local and systemic corticosteroids. The age in Group I ranged from 17 to 66 years with a mean of 42 ± 16.51 years while the age in Group II ranged from 19 to 60 years with a mean of 39.4 ± 11.24 years. In Group I, 12 patients (80%) were male while 3 patients (20%) were female. In Group II, 9 patients (60%) were male while 6 patients (40%) were female. No past history was found in 18 patients (60%) while bronchial asthma was found in 8 patients (26.67%) and aspirin sensitivity was found in 3 patients (10%). Both bronchial asthma and aspirin sensitivity were found in one patient in Group II. Results: The mean Total nasal symptoms score (TNSS) were 22.33 ± 1.21 in Group I and 20.07 ± 3.31 in Group II. The mean Total Nasal Polyp Score (TNPS) were 4.67 ± 0.82 in Group I and 4.8 ± 0.862 in Group II. The mean LundMackay Score (LMS) were 10.87 ± 0.74 in Group I and 11 ± 0.66 in Group II. Conclusion: Patients treated by FESS have less residual symptoms, size and severity of residual polyps and rate of recurrence than patients treated medically