Aims To explore nurses' knowledge, attitudes and practices related to improving hospitalized patients' sleep. Design Integrative review. Data Sources We searched CINAHL, PubMed and PsycInfo electronically including a manual search of references listed within the relevant studies. Original, peer‐reviewed studies published in English between 2000 and 2022 evaluating nurses' sleep knowledge, attitudes, or practices to improve inpatients’ sleep were reviewed. Review Methods This review was guided by Whittemore and Knafl method and followed PRISMA guidelines to search the literature. Fifteen articles reporting nurses' sleep knowledge, attitudes or practices to improve inpatients’ sleep were included. The quality appraisal was done using the Mixed Methods Appraisal Tool version 2018. Results Inadequate training of nurses regarding sleep hygiene and insufficiency in sleep‐promoting practices were apparent. Most studies reported that nurses hold positive attitudes about sleep. The acuity of patients' health conditions affected their perception of sleep priorities. Lack of organizational sleep policies/protocols and coworkers' attitudes negatively impacted nurses' motivation to implement sleep hygiene interventions. Interventions reported in the studies were reducing noise and nursing interventions at night, using a clock for time orientation, earplugs, reducing light, keeping patients awake during the daytime, maintaining comfortable room temperature and managing patients' stress. These practices were hindered by poor knowledge, negative attitudes, patients' acuity and lack of sleep assessment tools. Conclusion It is essential to support nursing practice to improve patients' sleep in hospitals through interventions that target nurses' knowledge, attitudes and confidence towards implementing sleep hygiene interventions to improve patients' sleep and, consequently, their health outcomes during hospitalization. Impact This integrative review explored nurses' knowledge, attitudes and practices to improve patients' sleep during hospitalization. It revealed that expanding nurses' sleep knowledge and empowering them to implement sleep promotion practices are needed. Nursing educators and leaders need to be involved. No Patient or Public Contribution This paper is an integrative review and does not include patient or public contribution.