© 2021 American Society for Parenteral and Enteral NutritionBackground: The Global Leadership Initiative on Malnutrition (GLIM) published malnutrition identification criteria. The Mini Nutritional Assessment (MNA) is malnutrition assessment tool commonly used in older adults. This study aimed to determine prevalence of malnutrition and the relationship between the GLIM and the MNA long form (MNA-LF) and short form (MNA-SF) and energy-protein intake. Methods: A total of 252 older adult outpatients (aged 68.0 years, 61% females) were included. Malnutrition was defined according to the GLIM, MNA-LF, and MNA-SF. Food intake was assessed using the 24-h dietary recall. We analyzed the cutoff value on the MNA-LF score, MNA-SF score, and energy-protein intake for GLIM criteria–defined malnutrition severity with receiver operating characteristic analysis. Results: Malnutrition was present in 32.2%, 12.7%, and 13.1% of patients according to the GLIM criteria, MNA-LF, and MNA-SF, respectively. It was determined that 92.7% and 89.0% of patients, based on GLIM criteria, had malnutrition with the MNA-LF and MNA-SF, respectively. The daily energy-protein intake was less in patients with malnutrition according to GLIM, as in the MNA-LF and MNA-SF classifications (p <.05). For the MNA-LF and MNA-SF score, the cutoff value of 11 and 9 points for severe malnutrition (area under curve [AUC] 0.92; p <.001 and 0.90; p <.001), 22 and 11 points for moderate malnutrition (AUC 0.79; p <.001 and 0.76; p <.001) were determined. Conclusion: According to GLIM criteria, one-third of outpatient older adults were malnourished, whereas the prevalence was much lower applying both the MNA-LF and the MNA-SF.