To explore the association between malnutrition and risk of depression in the elderly. Relevant studies were searched in PubMed, Web of Science, the Cochrane Library, Scopus, and Embase from the establishment of the database to August 17, 2023. Two researchers independently screened the literature, extracted data, and evaluated the risk of bias in the included studies. Stata16.0 software was used for meta-analysis. A total of 8 observational studies were identified with 11 112 participants, of which 2771 elderly patients had depression. The meta-pooled results showed a significant correlation between nutritional status and depression risk (odds ratio (OR) = 2.03, 95% CI = (1.47, 2.81), P < 0.001). Subgroup analysis found that the malnutrition scores of different study types and the diagnostic methods of depression and malnutrition were correlated with the risk of depression. Malnutrition was associated with depression risk in the elderly. Further large-scale multicenter studies should be conducted to test and verify the results.