Aim To examine the role of Adult Protective Services' (APS's) nurses in helping abused, neglected and exploited older people, this study investigated how nurses' contribution differs from social workers. Though the majority of APS' workforce is staffed by social workers, some programmes also employ nurses. Design Secondary data analysis using convergent parallel mixed‐method design was conducted. Methods Using survey data from the National Adult Protective Services Association, 99 nurses' responses between October 2014 and August 2015 were analysed to examine their agency characteristics, training and qualities, job responsibilities and interprofessional collaboration. Results The majority of nurses work with social workers or other professionals using a multidisciplinary team (MDT) approach. Among those carrying a caseload, 69% (49 out of 71) of nurses work in conjunction with social workers. Out of all nurses, 64% (63 out of 99) indicated participation in at least one MDT. While the responsibilities nurses provided were similar to social workers, nurses were also able to provide healthcare related services, in their professional competencies, without referral. Conclusion Nurses in APS are in a privileged position to investigate mistreatment and provide/coordinate direct care for victims. Impact Not much was known about nurses who directly investigate elder mistreatment and provide services to victims. This study was the first to highlight the nursing workforce in APS, and described the nurses' unique contribution to the field. Nurses functioned as both social workers and healthcare professionals in APS. Since victims of elder mistreatment often suffer from negative physical, psychological and social consequences, having nurses in APS benefits victims to receive and the programmes in providing better care and services.