The aim of this study was to assess health economics evidence published to date on malnutrition costs in institutionalized or community-dwelling older adults. A systematic search of the literature published until December 2013 was performed using standard literature, international and national electronic databases, including MedLine/PubMed, Cochrane Library, ISI WOK, SCOPUS, MEDES, IBECS, and Google Scholar. Publications identified referred to the economic burden and use of medical resources associated with malnutrition (or risk of malnutrition) in institutionalized or community-dwelling older adults, written in either English or Spanish. Costs were updated to 2014 (€). A total of 9 studies of 46 initially retrieved met the preestablished criteria and were submitted to thorough scrutiny. All publications reviewed involved studies conducted in Europe, and the results regarding the contents of all the studies showed that total costs associated with malnutrition in institutionalized and community-dwelling older adults were considerably higher than those of well-nourished ones, mainly due to a higher use of health care resources (GP consultations, hospitalizations, health care monitoring, and treatments). Interventions to reduce the prevalence of malnutrition, such as the use of oral nutritional supplements, showed an important decrease in-hospital admissions and medical visits. Malnutrition is associated with higher health care costs in institutionalized or community-dwelling older adults. The adoption of nutritional interventions, such as oral nutritional supplements, may have an important impact in reducing annual health care costs per patient.