Objective To optimize lighting management in neonatal wards to improve the sleep quality of preterm infants and enhance the quality of nursing care. Methods Guided by the JBI Model for Evidence-Based Healthcare, a multidisciplinary evidence-based practice team was formed. From an initial set of 29 summarized evidence statements, six core recommendations were selected and operationalized into 11 auditable criteria. A baseline audit was conducted from January to March 2025 involving 60 neonates and 51 nurses, followed by identification of barriers and facilitators. An evidence-based intervention was then implemented, and a post-implementation audit was carried out from June to August 2025 with the same sample size. Outcomes were evaluated using a knowledge questionnaire, compliance rates with the audit criteria, and neonatal physiological indicators，including heart rate variability, frequency of oxygen saturation <0.90, and daily sleep duration. Results Following the implementation, compliance with all 11 audit criteria significantly improved, with seven reaching 100% adherence (all P<0.05). Nurses′ knowledge scores on lighting management increased significantly from 33.00 (32.00, 37.00) to 39.00 (37.00, 41.00) (P<0.05). Neonates exhibited significantly reduced daily heart rate variability and significantly increased total sleep duration (both P<0.001), while the frequency of oxygen desaturation events showed no significant change (P>0.05). Conclusion Systematic implementation of an evidence-based lighting management protocol in neonatal units effectively enhances nurses′ knowledge and clinical adherence, and improves heart rate stability and sleep quality among preterm infants.