Aims and methodA survey was conducted to investigate physical assaults against mental health staff of a Nigerian psychiatric hospital in a 12-month period and also during their working career in the hospital retrospectively using a questionnaire method.ResultsIn total, 101 out of 120 questionnaires were completed (response rate 84.2%). Within the period of their employment in the hospital 49.5% of staff had been physically assaulted at least once, and over the previous 12 months 33.7% had been physically assaulted. Nursing staff (82.3%) were more frequently assaulted than doctors, most often during routine assessment of patients (44.3%). In total, 88% of staff sustained injuries requiring medical attention. Vulnerability to assaults was not associated with attending a course on prevention and management of psychiatric patient violence.Clinical implicationsAssaults by patients against mental health staff, especially nurses, are quite widespread in Nigeria. There is a need to formulate policies on prevention and management of violence in people with mental disorders in Nigerian psychiatric hospitals.