We aimed to investigate the prevalence of metabolic syndrome in rural and urban areas in the province of Segovia, Spain, and its relationship to lifestyle habits, cardiovascular risk, and serum adiponectin concentrations. The study had a cross-sectional design and included 888 individual residents in the province of Segovia, Autonomous Community of Castilla-León. The age/sex standardized prevalence of the metabolic syndrome was by: (1) American Heart Association/National Heart Lung and Blood Institute criteria (AHA/NHLBI), 17%; (2) International Diabetes Federation (IDF), 24.3%; and (3) Consensus Societies/Joint Interim Statement (CS), 27.8%. A high correlation was found between the different criteria. No formal education odds ratio (OR) 6.9 (2.4-20.2) and primary education 6.7 (2.8-15.9) were independently associated with metabolic syndrome. An inverse association with metabolic syndrome was found for subjects doing a high level of exercise during work 0.4 (0.2-0.7) as well as those who were mild drinkers alcohol intake of less than 15 grams/daily, 0.4 (0.3-0.8). Among subjects with low estimated cardiovascular risk, adiponectin levels are higher in those who do not meet criteria of metabolic syndrome. A total of 29.7% of subjects meeting CS criteria had >20% 10-year predicted risk of cardiovascular disease (CVD) by the Framingham risk score criteria 4.5 (2.4-8.5). Our results show: (1) A higher estimated prevalence of metabolic syndrome according to IDF and CS criteria. (2) Low educational level was independently associated with metabolic syndrome. A high level of physical activity and a daily alcohol intake of less than 15 grams/day were inversely associated with metabolic syndrome. (3) Metabolic syndrome increases the predicted CVD risk. (4) Adiponectin levels are not inversely related to insulin resistance in subjects with high cardiovascular risk and metabolic syndrome.