Background: The association between mental health and work has led to multiple meanings and definitions, leading to generalizations and equivalences that do not always reflect similar meanings. Objectives/Methods: To map and analyze the definitions of mental health related to work in the literature and identify the professional practices arising, a systematic review was carried out following PRISMA 2020 guidelines. Six databases were selected for consultation, which was carried out in March 2023. Results: From the search, 26 articles were selected and most of them do not define the concept of mental health, nor the influence of work on mental health–illness processes. Few articles report working conditions and the professional environment as generators of stress. Even if these conditions exist, the studies highlight that individuals already had previous personality traits that made them susceptible to disorders. Conclusions: Failure to adopt clear theoretical–methodological references regarding the concept of mental health and its relationship with work weakens the field and professional practice. Moreover, the literature does not point to changes in work or indicate possibilities for returning to assisted/ compatible work, vocational reorientation, or other means of overcoming the problem within work and organizations, with significant impacts on the design of public policies in the field.