Humor utilized in the practice of forensic mental health nursing might seem somehow inappropriate, given the serious circumstances surrounding most forensic mental health patients. However, some recent research has pointed to the use of humor as an important component in staff interactions with forensic mental health patients. This study reviews the existing international forensic mental health research literature on humor to investigate (a) what characterizes forensic mental health staff–patient use of humor and (b) what significance humor holds within the forensic mental health setting. The search was conducted in June 2013. Scopus, CINAHL, PubMed, and PsychINFO were searched using keywords relevant to the study. Articles were categorized using a literature matrix and analyzed using thematic analysis. Twelve research articles were reviewed and included in the analysis. Three themes were identified: (a) “humor as staff skill,” showing that staff found humor to be important as an interpersonal ability; (b) “humor as a relational tool” with the purpose of establishing and maintaining staff–patient interactions; and (c) “the impact of humor on patients,” describing impacts on conflicts, dimensions of health, and motivation. The results of the analysis are however limited because of the dearth of published articles on the subject.