BACKGROUND: The signs and symptoms of sinonasal sarcoidosis are diverse and nonspecific. It easily mimics more common sinonasal disorders such as allergic rhinitis, bacterial sinusitis, and atrophic rhinitis. The purpose of this study was to develop a classification system of sinonasal sarcoidosis that will help serve as a guide for both diagnosis and treatment. METHODS: A retrospective chart review was performed of all patients diagnosed with sinonasal sarcoidosis from 1974 to 2013. A PubMed literature review of all published case series of sinonasal sarcoidosis was also reviewed. RESULTS: The charts of 14 patients with biopsy-proven sinonasal sarcoidosis were reviewed. Follow-up time ranged from 6 months to 28 years. Presenting signs included hypertrophic mucosa, nasal polyps, crusting, nasal enlargement, and destructive processes. Eight patients underwent medical management alone and six patients underwent endoscopic sinus surgery. Five of the six patients were successfully treated with surgery. On review of the literature, 256 cases of sinonasal sarcoidosis were found, of which 43 patients underwent surgery. Clinical outcomes of the patients who underwent surgery were not consistently reported. CONCLUSION: Based on critical analysis of the clinical presentation of sinonasal sarcoidosis in our case series and on review of the literature, sinonasal sarcoidosis can be classified into four subgroups: atrophic, hypertrophic, destructive, and nasal enlargement. Each subgroup responds differently to treatment and has its own differential diagnosis. Surgery is only indicated for a select group of patients and the vast majority of patients benefit from medical management alone.