Metabolic syndrome (MetS) is a multifactorial cluster of metabolic disorders related to cardiovascular disease and type 2 diabetes mellitus. Diet and dietary patterns are significant factors in the development and management of MetS. The associations between dietary patterns (i.e., high-carbohydrate [HCHO], high-fat [HF], and high-protein [HP] diets) and the prevalence of MetS in Koreans were examined using data from the Korean National Health and Nutrition Examination Survey, collected between 2018 and 2020. The study included data from 9069 participants (3777 men and 5292 women). The percentage of participants with MetS was significantly higher in the HCHO diet group than in the normal diet group in women. Women with HCHO diet were positively associated with elevated blood pressure and triglyceride levels based on a comparison with the normal diet group (p= 0.032 andp= 0.005, respectively). Men with an HF diet were negatively associated with elevated fasting glucose levels based on a comparison with the normal diet group (p= 0.014). Our findings showed that HCHO intake was strongly associated with a higher risk of MetS, especially elevated blood pressure and triglyceride levels in women, and an HF diet was negatively associated with elevated fasting glucose levels in men. Further prospective studies of the impact of dietary carbohydrate, fat, and protein proportions on metabolic health are needed. The optimal types and proportions of these dietary components, as well as the underlying mechanisms through which suboptimal proportions can lead to MetS, should also be investigated.