OBJECTIVES: There is ongoing debate regarding the effectiveness of open cavity mastoidectomy (OCM) versus closed cavity mastoidectomy (CCM) in patients with chronic otitis media (COM). This study aimed to compare audiological outcomes of OCM and CCM in cholesteatomatous COM (CCOM) patients. METHODS: Clinical data were collected from 102 patients with middle ear cholesteatomas who underwent OCM or CCM for CCOM at our hospital between February 2018 and May 2022. A retrospective analysis was conducted on audiological outcomes for patients with CCOM receiving either OCM or CCM. Air conduction (AC), bone conduction (BC), and air-bone gap (ABG) were compared between the two surgical methods. Further, recurrence, complications, pathological types, and the impact of prior ossiculoplasty were analyzed both before surgery and at three months post-ossiculoplasty. RESULTS: No significant differences in demographic features were observed between the OCM and CCM groups, including gender, age, complications, pathological types, and the use of ossiculoplasty. All cases presented with hearing loss and otorrhea. Both OCM and CCM significantly reduced AC, BC, and ABG thresholds, with OCM showing greater effectiveness in decreasing AC and BC thresholds compared to the CCM method. In patients with different pathological types, OCM did not result in a significantly greater reduction in AC, BC, or ABG thresholds compared to CCM. Further, there were no significant differences in hearing outcomes between OCM and CCM, regardless of whether patients underwent ossiculoplasty. CONCLUSIONS: Both OCM and CCM are effective in improving hearing in patients with CCOM. However, OCM demonstrates superior therapeutic effects compared to CCM, particularly in terms of effectiveness, although complications and drying time should be considered.