Introduction: Diseases of the Para nasal sinuses include wide spectrum ranging from inflammatory conditions to neoplasms.Computed tomography(CT) has replaced conventional radiographs as imaging modality of choice for assessment of Para–nasal sinus diseases.Objectives:To evaluate the pathologies affecting the Paranasal sinuses and the anatomical variants by Computed Tomography.Methods: A Cross sectional study was conducted at RIMS from June 2018 to June 2019 among 130 patients of varied age group presenting with symptoms and signs of paranasal sinus diseasesreferred for CT of paranasal sinuses. Results:The CT diagnosis shows sinusitis (73.0%) to be the most common sinus lesion found in patients followed by polyposis (23.8%), fungal sinusitis (1.6%), neoplasm (6.2%) and inverted papilloma (0.8). The most common anatomical variant was found to be deviated nasal septum (55.4%) followed by agger nasi (49.2%) and concha bullosa (29.2%). Conclusion: Most common sinonasal pathology in patients with PNS disease was inflammatoryand maxillary sinus is most commonly affected. Deviated nasal septum accounts for more than half of the anatomical variant followed by agger nasi and concha bullosa.