Background:  In paranasal sinus disease, local  examination is limited as sinuses cannot be examined directly. Objective: This study was carried out with an objective to evaluate and compare  CT scan findings and Nasal endoscopy findings in patients with paranasal sinus disease. Methods: 30 cases of chronic Rhinosinusitis not responding to routine medical  treatment were operated after  CT scan  and nasal endoscopy.   Both investigative modalities were compared to each other and correlated with operative findings. Results and conclusion: A high association was found between both the modalities i.e. CT scan and nasal endoscopy with one scoring over the other in different parameters. Nasal endoscopy is found to be highly specific for  anatomical variants in the osteomeatal complex, whereas CT scan is highly sensitive for parameters like frontal recess pathology and sphenoethmoid recess disease. So, a case of sinus disease should be diagnosed  using both these modalities as together they complement each other.