Background: Chronic rhinosinusitis (CRS) is a persistent inflammation of the nasal mucosa and paranasal sinuses. Anatomical variations of the nasal and paranasal sinuses can obstruct and impair the drainage and ventilation functions of the sinus ostium, causing CRS. Objective: To determine the correlation between nasal and paranasal sinus anatomical variations with the degree of severity of CRS based on a CT scan at Dr. Zainoel Abidin Hospital. Methods: An analytic observational study with a cross-sectional design from the results of CT scans of CRS patients in the period on October 2019-october 2022. The anatomical variations assessed were the degree of deviation of the nasal septum, type of bullous turbinate, paradoxical turbinate, hypertrophy of ethmoid bullae, Haller cells, deflection of uncinate process, type of superior insertion of the uncinate process, pneumatization of the uncinate process and frontal sinus cells to the degree of CRS using the Lund Mackay score. Data were analyzed using the Chi-Square test or Fisher's exact test. Result: Analysis of 64 CT scans consisting of 128 sides of the nose found a significant relationship between anatomic variations and the degree of CRS, namely the degree of deviation of nasal septum, type of concha bullosa, ethmoid bulla hypertrophy and deflection of the uncinate process to the severity of maxillary sinusitis (p=0.023; p=0.024; p=0.039; p=0.029) and paradoxical medial concha for the severity of maxillary sinusitis, anterior and frontal ethmoiditis (p=0.018; p=0.013; p=0.000) Conclusion: Anatomical variations of the nasal and paranasal sinuses are related to the severity of CRS.