Objective To investigate the expression level of Superoxide Dismutase (SOD) in eosinophil invasive chronic rhinosinusitis (eosinophilic chronic rhinosinusitis, eCRS) and non-eosinophilic invasive chronic rhinosinusitis (non-eosinophilic chronic rhinosinusitis, non-eCRS). Methods The clinical data of 286 eCRS and non-eCRS admitted to our hospital from June 2022 to December 2023 were retrospectively analyzed. The pathological type grouping of chronic rhinosinusitis was classified according to the number of eosinophil infiltration in the postoperative pathological sections, and the patients were classified as eCRS and non-eCRS. Results The expression of SOD was lower in the eCRS group than in the non-eCRS group, statistically significant (P <0.05), and a negative correlation with whether chronic sinusitis was eosinophil infiltrating (P <0.05). Conclusion The expression of SOD was lower in eCRS patients, and there is a correlation between SOD expression and whether eosinophil infiltration type in chronic rhinosinusitis.