Introduction: This study aimed to determine the effect of listening to music during the postoperative period on pain and anxiety levels in women who underwent cesarean delivery. Methods: This randomized controlled trial included 110 women who had undergone cesarean section between February and July 2024. Beginning at the 24th postpartum hour, women in the intervention group listened to relaxing classical music for 15 min every hour, while no intervention was applied to the control group. A standardized playlist of instrumental classical music (e.g., works by Mozart, Vivaldi, and Debussy) was created to induce relaxation and ensure consistency across participants. At the 48th postpartum hour, both groups were assessed using the Descriptive Characteristics Form, the Postpartum-Specific Anxiety Scale (PSAS), and the Pain Catastrophizing Scale (PCS). Results: Women in the intervention group listened to an average of 72.02 ± 3.14 min of music. The mean scores on the PSAS and PCS were significantly higher in the control group than in the intervention group (p < 0.001). Discussion: The findings indicate that listening to relaxing classical music significantly reduces postpartum anxiety and perceived pain. These results support the incorporation of culturally appropriate, music-based non-pharmacological strategies into routine postpartum care following cesarean delivery. This trial is registered at ClinicalTrials.gov under the title “The Effect of Music Postoperative Period (EMPP)” (Registration No: NCT07164521, https://clinicaltrials.gov/study/NCT07164521).