Background: Nasal Polyposis are treated with topical steroids, systemic oral steroids, surgical excision, and intrapolyp steroid injection. Local and systemic steroid treatment is the mainstay of therapy for nasal polyposis. Objectives: The aim of this study was to evaluate the role of intrapolyp steroid injection in the treatment of nasal polyposis and its efficiency, and to compare these results with that of oral and topical nasal spray corticosteroid. Patients and Methods: This study involved 60 patients presented at ENT Outpatient Clinic, Al-Zahraa University Hospital and diagnosed as nasal polyposis. Their age ranged between (18-60) years. They were randomly divided according to type of treatment (nasal corticosteroid spray, oral corticosteroid and intranasal injection of corticosteroid) into 3 groups, each consisted of 20 patients. Results: There were statistically significant differences in total nasal symptom score (TNSS), nasal polyp score (TNPS) and endoscopic analysis. It has been noted that in nasal spray group, Improvement of symptoms with No Regression of Polypis observed in 13 patients (65%) and no change at all in 7 patients (35%). While in oral steroids group, complete regression is observed in 4 patients (20%), partial improvement in 11 patients (55 %), and no response in 5 patients (25%) and in injection group, complete regression of polyps is observed in 2 patients (10%), partial improvement in 13 patients (65%), and no change at all in 5 patients (25%). Conclusion: It could be concluded that intrapolyp steroid injection could be considered one of the alternative treatments of sinonasal polyposis as it is effective, easy, and safe procedure and its effect lasts for at least 3 months.