Growing research underscores the significance of diet quality in the development of Metabolic Syndrome (MetS). Our study investigates the correlation between the Global Diet Quality Score (GDQS) and MetS, along with its components, in Iranian adults. This study utilizes data from the Yazd Health Study (YaHS) and includes a final analysis of 2,904 participants aged 20-70 years. Dietary data were gathered using food frequency questionnaires. MetS was defined in line with the National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III) criteria. GDQS was derived by totaling the points across all 25 food groups, with scores ranging from 0 to 49. To examine the association between GDQS and MetS, multivariable logistic regression analyses were conducted in both crude and adjusted models. Participants who had the highest adherence to GDQS had a 20% lower chance of having MetS than those who had the lowest adherence after adjusting for confounding variables in Model II (T3 vs. T1: OR = 0.80; 95% CI: 0.46-0.99, P-trend = 0.045). There was no association between GDQS and MetS components including increased blood pressure, fasting blood glucose (FBG), triglyceride, abdominal obesity and reduced high-density lipoprotein (HDL) in crude and adjusted models. higher adherence to GDQS was inversely related to odds of MetS. Further longitudinal and clinical trials investigations are required to confirm these associations.