OBJECTIVES: Postoperative delirium is a frequent complication with possible detrimental consequences in older hip fracture patients. Music interventions are promising, with positive effects on risk factors for delirium. This study aimed to assess the impact of perioperative music on postoperative delirium in older hip fracture patients. DESIGN: Prospective randomised controlled trial. SETTING: Multicentre study, performed in six participating hospitals in the Netherlands. PARTICIPANTS: Eligibility criteria included patients aged ≥65 years with an acute hip fracture requiring surgery and documented informed consent. 449 patients were randomised, with a median age of 81 years (IQR 74-87), including 287 women (63.9%). INTERVENTIONS: Music group participants received the intervention preoperatively, intraoperatively, and postoperatively twice a day for 30 min. The control group received standard-of-care, supplemented by headphones without music intraoperatively for equal noise reduction in both groups. PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome was delirium diagnosis (Diagnostic and Statistical Manual of Mental Disorders, fifth edition), assessed by a geriatrician. Associations were analysed using regression models. Secondary outcomes included: Delirium Observational Score, anxiety, pain and postoperative complications. RESULTS: Intention-to-treat analysis showed no statistically significant decrease of delirium in the music group, compared with the control group (OR 0.685 (95% CI 0.378 to 1.242); p=0.21). However, in the modified-intention-to-treat analysis, a significant decrease in postoperative delirium was observed (OR 0.478 (95% CI 0.245 to 0.933); p=0.028), which is substantiated by a logistic regression (OR 0.43 (95 % CI 0.19 to 0.98); p=0.045). Also, more postoperative complications were observed in the control group (93 (43.3%); 66 (32.7); p=0.026) in this analysis. The intervention was associated with high patient satisfaction and no adverse events. CONCLUSIONS: This study suggests a positive effect of music interventions on postoperative delirium, which provides additional evidence for considering the implementation of these interventions in hip fracture care. TRIAL REGISTRATION NUMBER: International Clinical Trial Registry Platform, Dutch Trial Register (www.onderzoekmetmensen.nl/, ID:NTR7036).