Background - Mental illness is a major problem within prison settings. Inadequate and insufficient mental health care contributes to prisoners' mental illness. Proximity to the prisoner, a respectful attitude and good relations between prison officers and prisoners are some factors that promote mental health.

Aim - The aim was to describe prison officers' view of their caring work with prisoners with mental illness in a prison environment.

Method - An empirical study was made using qualitative interviews with eight prison officers. The interviews were analysed and thematised with a content analysis. Ethical implications have been considered during the study.

Results - The results revealed that the prison officers considered it important to build relationships and pay attention to the prisoner, but that the institutional environment and lack of resources was described as difficulties while working. Balancing security and building relationships were also considered as difficult. Despite these factors, the prison officers experienced that they managed to create good relationships and a good atmosphere with the prisoners in the prison environment. Conclusion - Despite similarities in what previous research defines as care and how the prison officers are working with the prisoners with mental illness, they did not define their work methods as caring. The study implicated that an awareness of the definition of caring helps to improve prison officers' caring work within prison settings