The aim of this study was to evaluate the association between the serum levels of prealbumin and sarcopenia in older adults with type 2 diabetes mellitus.This cross-sectional study included 582 older adults with type 2 diabetes mellitus. Sarcopenia was defined based on the recently updated Asian Working Group for Sarcopenia 2019 criteria. Appendicular skeletal muscle was measured by dual energy x-ray absorptiometry. Serum levels of prealbumin, hemoglobin, hemoglobin A1c, and 25-hydroxyvitamin D3 were also tested. Multivariate analyses were used to assess the association between prealbumin levels and sarcopenia, adjusted for potential confounders.The overall prevalence of sarcopenia was 9%, of which 12% for men and 6% for women. Male participants with sarcopenia had lower prealbumin levels than those without sarcopenia (213 ± 72 versus 260 ± 56 mg/L, P < 0.001). The proportion of men with low prealbumin level (<170 mg/L) was significantly higher in individuals with sarcopenia than in those without (31% versus 6%, respectively). In a logistic regression model, after adjusting for all potential covariates, low prealbumin (odds ratio, 4.15; 95% confidence interval, 1.13-15.25; P = 0.03) was significantly associated with sarcopenia in men, but the relationship between prealbumin and sarcopenia was not found in women.Low prealbumin levels were associated with an increased risk for sarcopenia in older men with T2DM.Copyright © 2021 Elsevier Inc. All rights reserved.