ABSTRACT: Objective: To analyse different sino-nasal diseases causing proptosis in patients presenting in ENT department. Study Design: Retrospective descriptive study. Settings: Department of ENT and Head & Neck surgery, Allied Hospital, Punjab Medical College Faisalabad. Period of study: Two years (June 2014 to May 2016). Patients and Methods: This study consisted of 30 patients who presented with history of proptosis because of some sino-nasal disease. Inclusion criteria: Patients having unilateral or bilateral proptosis of either sex with some lesion in the sino-nasal region. Exclusion criteria: Patients with proptosis due to endocrine and ophthalmological causes. Data Analysis: SPSS software, version 10 was applied to analyse the data. Chi square test was used to analyse the data. Results: Out of 30 patients; 56.6% were males and 43.4% were females ranging from 06 to 67 years with mean age of 34.3 years. In this study 70% of the patients had unilateral proptosis while 30% patients presented with bilateral proptosis. Different sino-nasal diseases causing bilateral proptosis were observed in this study. We found bilateral allergic nasal polyps in 3.3%, bilateral allergic fungal rhinosinusitis in 16.6% and both allergic nasal polyps and fungal rhinosinusitis in 10% of the patients. The remaining 70% of the patients having unilateral proptosis had nasal polyps in 6.7% , allergic fungal rhinosinusitis in 10% and both nasal polyps and fungal rhinosinusitis in 6.7% of the patients. Fungal ball in the maxillary sinus was diagnosed in 6.7% of the patients. Among 15 patients with fungal disease and proptosis 10 patients (66.7%) were immunocompetent whereas the remaining 05 patients (33.3%) were immunocompromized and metabolically moribund. Fronto-ethmoidal mucoceles in 6.7%, juvenile nasopharyngeal angiofibroma in 6.7%, inverted papilloma in 13.3% and malignant growths of nose and paranasal sinuses were diagnosed in 13.3% of the patients. 16.6% patients were smokers, another 16.6% were diabetic and 13.3% of the patients had hypertension. Treatment: All the patients underwent different surgical procedures to treat the basic pathological lesions causing unilateral or bilateral proptosis aiming at total clearance of the disease and orbital repositioning. Conclusion: Undoubtedly a number of sino-nasal diseases can cause either unilateral or bilateral proptosis but fungal infection of the nose and paranasal sinuses is quite a common cause and is increasing day by day even in young, healthy otherwise immunocompetent patients. These patients need awareness programs regarding importance of early diagnosis and prompt treatment to prevent fungal rhinosinusitis and hence to manage proptosis.