This qualitative study aimed at investigating how mental health nurses acquired knowledge about the theme family during their academic training, how they see families in their daily practice, and how should professional training be considering the presence of the family in the care setting. Data were collected using semistructured questionnaires. Six nurses were interviewed. Data analysis allowed the establishment of three theme categories: Academic and professional training absence of the family theme; the nurses' perception of the family with a mentally ill member; and a new vision of the family the role of teaching. During undergraduate education, nurses acquired little knowledge about the theme family; in the institutional routine, they praise the family as a participant of care; and indicate that the need for knowledge about families is based on the interdisciplinary character of education.