This study aimed to evaluate a team-based systematic prevention and management program for delirium (a multicomponent intervention addressing potentially modifiable risk factors based on the DELirium Team Approach [DELTA]) in older patients undergoing orthopedic surgery within a real-world clinical setting. The DELTA program was initiated at our hospital in January 2019. A retrospective before-after study was conducted during a preintervention period (January 1, 2017 to December 31, 2018) and a postintervention period (January 1, 2020 to December 31, 2021) at orthopedic wards of an advanced acute care hospital in Japan. A total of 787 inpatients were evaluated before the preintervention period, and 833 inpatients were evaluated after the postintervention period. After the DELTA program's implementation, a significant decrease in benzodiazepine receptor agonist prescriptions (odds ratio [OR], 0.39; 95% confidence interval [CI], 0.29-0.53) and an increase in prescriptions of either melatonin receptor agonists or dual orexin receptor antagonists (OR, 3.83; 95% CI, 2.49-5.88) were observed. However, no significant difference was observed in the incidence of falls, self-extubation, or required level of medical and nursing care, including risky behavior and inability to follow medical or care instructions following the intervention, despite a reduction in the length of hospital stay and institutionalization. Implementing the DELTA program for older patients undergoing orthopedic surgery contributed to optimizing the prescription of hypnotics; however, the impact on other patient outcomes, such as falls, self-extubation, and required level of medical and nursing care was limited.