Aims: The aim of this review was to synthesize the best available evidence on the impact of nurses' safety attitudes on patient outcomes in acute-care hospitals. Design: Systematic review with a narrative synthesis of the available data. Data sources: Data sources included MEDLINE, Cumulative Index of Nursing and Allied Health Literature, Scopus and Web of Science Core Collection. Studies published up to March 2021 were included. Review Methods: This review was conducted using guidance from the Joanna Briggs Institute for Systematic Reviews and reported as per the Preferred Reporting Items for Systematic Review and Meta-Analyses guidelines. Results: A total of 3,452 studies were identified, and nine studies met the inclusion criteria. Nurses with positive safety attitudes reported fewer patient falls, medication errors, pressure injuries, healthcare-associated infections, mortality, physical restraints, vascular access device reactions and higher patient satisfaction. Effective teamwork led to a reduction in adverse patient outcomes. Most included studies (N = 6) used variants of the Hospital Survey on Patient Safety Culture to assess nurses' safety attitudes. Patient outcomes data were collected from four sources: coded medical records data, incident management systems, nurse perceptions of adverse events and patient perceptions of safety. Conclusion: A positive safety culture in nursing units and across hospitals resulted in fewer reported adverse patient outcomes. Nurse managers can improve nurses' safety attitudes by promoting a non-punitive response to error reporting and promoting effective teamwork and good communication.