What is known on the subject?: It is generally felt that it is helpful for mental health nurses to control their emotions during their work. There are different approaches, but there is growing acceptance that different emotions may need different coping strategies. There is lots of evidence that nurses sometimes feel anger in a number of situations, but the research about anger in mental health nurses has never been examined as a whole. What this paper adds to existing knowledge?: We have systematically identified all previous research where nurses completed measures that tried to measure their anger in certain situations, compared it to other people or investigated how it affected them or what its relationship was with their practice. Only a few studies have measured nurses’ anger. However, it seems that while nurses are not generally angrier than any other group, they do often feel anger in relation to management of patient aggression and their job situation more generally. What are the implications for practice?: Anger is the most commonly reported problematic emotion for mental health nurses. It may influence their practice and affect their well-being. This has implications for staff support and training. Abstract: Introduction Emotional regulation is important in mental health nursing practice, but individual emotions may require different regulation strategies. There is ample evidence that nurses experience anger specifically during their work, for example when experiencing patient aggression. It is, therefore, important to consolidate what is known about how anger manifests in mental health nursing practice. Aim: We aimed to systematically identify, evaluate and synthesize results from studies about mental health nurses and anger, where anger was measured objectively. Methods: Systematic literature review based on PRISMA guidelines. Results: We identified 12 studies. A range of validated and nonvalidated instruments was used. Mental health nurses may have lower levels of anger than normative samples, but anger is commonly reported as an issue for them. Anger was studied in relation to its links with (1) clinical management of patients, notably violence containment; and (2) employment issues more generally, notably job motivation. Anger is related to nurses’ attitudes about the acceptability of coercion, but there is no evidence that it results in more coercion. Implications for practice: Nurses should be aware of the potential influence of anger on their practice. Anger, specifically, should be considered when supporting mental health nurses, for example in clinical supervision. Emotional regulation training should target anger.