Purpose: Sarcopenia is an age-related disorder characterized by a decrease in muscle mass, grip strength, and physical capacity. Large cohort studies evaluating sarcopenia and diet quality have been lacking and have yielded inconsistent results. This study was undertaken to investigate the relationship between diet quality and skeletal muscle mass in 40-69 year adults. Methods: All data for this study were obtained from a population-based prospective cohort study, the Korean Genome Epidemiological Survey (KoGES). A total of 1,124 men and women aged 40 to 69 years, residing in Ansung who participated in KoGES, were followed up every 2 years from 2001-2002 to 2013-2014 to confirm low skeletal muscle mass. We estimated skeletal muscle mass by applying lean body mass; the skeletal muscle mass was estimated by dividing the body weight and multiplying by 100 to express the skeletal muscle mass index (SMI). A Cox proportional hazard regression model was used to analyze the hazard ratio (HR) and 95% confidence intervals of low SMI according to diet quality at baseline and was gender-specific. Results: During the 12-year follow-up period, a total of 413 subjects (36.7%) had low SMI. This study did not find any significant association between diet quality and low SMI. Conclusion: Although ...