The purpose of the study is to investigate mental health nurses' experiences of recognizing and responding to suicidal behavior/self-harm and dealing with the emotional challenges in the care of potentially suicidal inpatients. Interview data of eight mental health nurses were analyzed by systematic text condensation. The participants reported alertness to patients' suicidal cues, relieving psychological pain and inspiring hope. Various emotions are evoked by suicidal behavior. Mental health nurses seem to regulate their emotions and emotional expressions, and balance involvement and distance to provide good care of patients and themselves. Mental health nurses have an important role and should receive sufficient formal support.