Introduction Chronic oral mucosal diseases (COMDs) can significantly impair the quality of life (QoL) of affected individuals. Monitoring the overall disease’s impact and the efficacy of treatments requires the use of the Chronic Oral Mucosal Diseases Questionnaire-15 (COMDQ-15) as a standardized instrument for measuring QoL in these patients. Objective This study aimed to assess QoL in patients with COMDs using an Indonesian version of the COMDQ-15. Methods Seventy patients diagnosed with recurrent aphthous stomatitis (RAS), oral lichen planus, autoimmune blistering diseases (ABD), and cheilitis were included. Levels of QoL among different groups of disease were compared. Various potential factors influencing QoL were evaluated. Bivariate analysis was performed to identify factors associated with overall and specific aspects of QoL. Results The mean total COMDQ-15 score was 20.83 ± 10.07. The highest scores were in the physical discomfort domain (8.76 ± 4.65), while the lowest was in the medication and treatment domain (2.13 ± 1.99). Physical discomfort was significantly associated with gender, major RAS, and cheilitis. Social and emotional aspects were significantly associated with age and ABD, while patient support was linked to employment status, RAS types, and cheilitis. Conclusions The Indonesian version of the COMDQ-15 is a valid and reliable tool for assessing QoL in patients with COMDs.