Whether serum homocysteine levels are associated with coronary heart disease (CHD) and the metabolic syndrome (MS) needs investigation in different ethnic groups. These associations and the influence of serum folate and vitamin B 12 thereupon were addressed separately in genders.A random sample of Turkish adults was studied cross-sectionally.Median age of 338 men and 342 women was 55 years. Geometric mean serum homocysteine concentrations were 12.7±1.5μmol/l in men and 9.6±1.4μmol/l in women (p<0.001). Linear regression analysis among 11 variables revealed male sex, reduced estimated glomerular filtration rate (eGFR) and vitamin B 12 , (in men) reduced folate as significant independent covariates of higher homocysteine levels. Logistic regression analysis disclosed that (sex-specific) top versus bottom homocysteine tertile was borderline significantly and independently associated with CHD in men and both genders combined, after adjustment for gender, age, smoking status, systolic blood pressure, eGFR, folate and vit B 12 . Folate revealed significant inverse association with CHD likelihood in men and combined genders (OR 0.73 for doubling [95%CI 0.56; 0.94]), independently of homocysteine levels and even of presence of type-2 diabetes. Serum vit B 12 concentrations were significantly associated with MS likelihood in women alone after adjustment for sex, age, smoking status, folate and antidiabetic medication.High serum homocysteine and low folate levels are associated in Turkish men independently with CHD, which needs confirmation in a larger sample. In women, vitamin B 12 concentrations are significantly associated with MS likelihood.