Objectives: Depression rates are substantially higher among older adults in long-term care when compared with older adults in the community. Furthermore, the needs of older adults in long-term care are increasingly complex, and risk factors that contribute to depression in this population are unclear. This limits not only the identification of those at risk for depression but also the development of therapeutic interventions. This review summarizes the evidence on risk factors for depression. Methods: Searches were performed using CINAHL, Cochrane Library, Ovid Medline, PsycINFO and Scopus for research published 1980–2017. Data were reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Results: Eleven studies met the inclusion criteria, representing a total of 11,703 participants, with a mean sample size of 1,064. The most consistently supported risk factor was cognitive impairment, followed by functional impairment and baseline depression score. Conclusions: The studies lacked a systematic approach to investigating risk factors for depression, and the research remains largely atheoretical. Few risk factors were consistently studied, with over 20 risk factors examined no more than once each. Psychological and environmental risk factors, which may be modifiable and have the potential to inform therapeutic interventions and preventative strategies, remain under-studied. Clinical Implications: The most consistently supported risk factors—cognitive impairment, functional disability and baseline depression score—have the potential to inform screening protocols and should be monitored longitudinally. When developing psychotherapeutic interventions, close consideration should be given to cognitive and functional impairment as barriers to implementation and uptake.