Recently, much of the world, including the World Health Organization, the European Union and many North American countries, have emphasized patient safety. Around the same time, Taiwan’s Department of Health (DOH) devoted a significant amount of resources to better the quality of medical treatment for their patients. This study explores perceptions of and attitudes towards patient safety among medical staff and patients in emergency departments. Analysis results indicate that medical staff and patients significantly differ in perceptions and attitudes. Results of this study provide a valuable reference for governmental authorities and hospital managers in formulating policies aimed at clarifying perceptions and attitudes regarding patient safety among medical staff and patients in emergency departments.