Systemic isotretinoin is commonly used for severe acne treatment. It has many side effects, one of these is about hearing system, which has rarely been reported, also previous studies reported contradictory results about systemic isotretinoin and its association with hearing system. In this study, we aimed to investigate whether systemic isotretinoin affected on the hearing system or not. The study included 32 acne vulgaris patients (64 ears) who treated with oral isotretinoin 0.5 mg/kg body weight for at least 4 months and audiometric tests including pure‐tone, speech, bilateral acoustic reflexes, and tympanometric measurements were performed at baseline, in the first week, in the first month, and third month of treatment, and sixth month after treatment. Audiometric tests were performed for right and left ears separately. A significant difference was found in the pure‐tone thresholds (before treatment, first week, first month, third month of treatment, and sixth month after treatment) for the both ears at 8000 Hz (P < .001) and a significant decrease in the sixth month post‐treatment pure‐tone thresholds compared to pre‐treatment thresholds at 8000 Hz. Additionally, a statistically significant increase was observed in serum LDL and triglyceride levels in the third month of treatment and a significant decrease at the sixth month after treatment (P < .001). Systemic isotretinoin caused bilateral hearing threshold changes in acne patients during the therapy but the changes improved after discontinuation. Therefore, our findings may provide safety using for dermatologists about hearing effects of isotretinoin, which is quite effective on severe acne.