Background: Sarcopenia is a disease associated with muscle changes during aging, and its detection remains a challenge outside specialized clinical units. Objective: To evaluate the utility of the Mini Nutritional Assessment (MNA) in detecting sarcopenia in institutionalized older persons. Materials and Methods: Cross-sectional study in adults aged 55 years and older from the city of Puebla. The MNA in its short form (SF) and full form (LF) were administered. The diagnosis of sarcopenia was made according to EWGSOP2. Points obtained from MNA-SF and MNA were plotted on a ROC curve. The odds ratio (OR) for presenting sarcopenia was evaluated according to recommended cutoff points with logistic regression models, adjusted for age and sex. Results: 162 participants were included, 64.1% were women, the mean age was 69.8 years (SD:5). The mean scores of MNA-SF and MNA-LF were 12.17 (SD:1.78), and 25.1 (SD:2.83), respectively. The prevalence of sarcopenia was 20.4%. The AUC of MNA-SF was 0.68 (95%CI:0.58-0.78) and for MNA-LF, 0.60 (95%CI:0.49-0.71). The OR for presenting sarcopenia with MNA-SF<12 was OR=2.87 (95%CI:1.31-6.29) and, after adjustment for age and sex, OR=2.47 (95%CI:1.10-5.54). Conclusions: According to AUC, MNA-SF may be useful in detecting sarcopenia in institutionalized older persons, while MNA-LF may have reduced utility in practice.