Introduction. Metabolic syndrome (MetS) is a noncommunicable disease with a high burden, including the development of type 2 diabetes mellitus, cardiovascular events, and death. It is characterized by abdominal obesity, elevated blood pressure, increased fasting plasma glucose levels, hypertriglyceridemia, and reduced levels of high‐density lipoprotein (HDL) cholesterol. MetS is preventable by modifying lifestyle and dietary patterns, which are major contributing factors. This research aimed to investigate the dietary patterns of the Shiraz Heart Study (SHS) and their associations with the occurrence of MetS and its components among middle‐aged residents of Shiraz. Methods. Based on data from the Shiraz Heart Study (SHS), a prospective cohort study, the nutritional status of 1,675 participants was assessed using a food frequency questionnaire (FFQ). Three food patterns were extracted from the analysis named as vegan, western, and carbohydrate. Subjects were categorized into three levels for three major dietary patterns: low, moderate, and high, based on their adherence to each pattern. After adjusting the effect of co‐founder variables, the relationship between dietary patterns, and the risk of developing MetS was analyzed. Results. Of the 1,675 participants, 728 (43.5%) of them were male. The prevalence of MetS was 47.2%. Multivariate logistic regression analysis showed that high adherence to the vegan pattern was negatively associated with the occurrence of MetS (P value <0.001), while low adherence to the western pattern was also negatively associated (P value <0.05). Conclusion. Healthier diets, such as vegan diets, are significantly related to lower rates of MetS among the 40–70‐year‐old people in Shiraz, Iran.