Background: Spouse caregivers play a vital role in the long-term care of chronically ill and dependent partners. They frequently experience caregiver burden with negative health outcomes. Caregiver burden is associated with poor mental health outcomes such as depression and anxiety among spouse caregivers. A caregiver's mental health is essential to the well-being of the caregiver and care recipient; thus, it needs to be accounted for in patient management and in caregiver studies.Objective: The purpose of this integrative review was to examine studies that explored relationships between caregiver burden and spouse caregivers' mental health.Methods: Searches in PubMed, Scopus, and CINAHL identified 18 studies that met the inclusion criteria. Twelve of the studies focused on spouse caregivers alone while six included family caregivers with spouse caregivers making up 50% or more of the sample.Results: Anxiety and depression were common among spouse caregivers but were often not measured or discussed. Most samples lacked racial and ethnic diversity. Mediating factors such as socioeconomic/income status which can influence mental health outcomes were rarely analyzed or reported. Functional and cognitive decline were the most common mediators of anxiety and depression. The heterogeneity of the methods and measures used in the studies could limit the generalization of findings.Conclusion: More studies are needed that include historically underrepresented spouse caregivers. Accounting for confounders such as level of education, income status, and elements of social determinants of health is essential in caregiver studies because of their strong influence on health and mental outcomes.