Background: Very few studies have shown the possible relationship between magnesium (Mg) status and depression. In the present study, the intracellular Mg status of the elderly population living in nursing homes (NHs) was assessed to determine its relationship with depression. Methods: A descriptive-analytical study was conducted on the elderly population living in nursing homes (Tehran-Iran; 2010-2012). Participants' demographic and clinical characteristics were collected and recorded in a checklist. Evaluating the participants’ nutritional status, Mini Nutritional Assessment Method was implemented. Determining participant's depressive symptoms, 15-item Geriatric Depression Scale was used. Final scores were classified into4 categories not depressed, mild, moderate, and severe depression. Mg level in leukocytes was also measured by flame atomic absorption spectrometry. Results: Totally 113 elderly were included and only 9.8% of subjects were not depressed. About 21% of the subjects were well nourished. Of participants who suffered from heart disease, 80.2% were depressed (p=0.03). Regarding correlations between Mg status and depression, results showed no significant difference in Mg levels of two depressed and non-depressed participants (p=0.73). Conclusion: The results of the present study showed notable prevalence rates of depression and malnutrition among nursing home residents. It was also found that the relationship between intracellular Mg levels and depression was not significant. Further studies are needed to determine the major factors related to these preventable psychological and nutritional disorders among elderly NH residents.