The sedative effects of music on healthy and sick individuals are known for centuries. Nowadays, nursing has used the efficacy of music therapy in interventions. The aim of the study was to determine the effect of music, which the patients undergoing a coronary angiography for the first time listened to during the intraoperative period, on the level of anxiety in the patients. The study was conducted experimentally as a pretest/posttest control group design. Data collection form; state-trait anxiety inventory, CDs and CD player were used. Inventories were applied to the patients before the process. The study group (100 patients) listened to music throughout the intervention, whilst the control group (100 patients) listened to no music. At the end of the process, all patients were given the same state anxiety inventory once more. The data was assessed by number, percentage, mean distribution with the paired t-test and t test. It was found that the difference between the mean state anxiety scores obtained before and during the coronary angiography were significantly higher in the study group (4.04 ± 1.15) than the control group (2.01 ± 0.10) (p = 0.000). It was concluded that the listened to during the coronary angiography process had an impact on the intraoperative anxiety levels of the patients.