Background/Aim. Vitamin D deficiency is a well-established risk factor for bone disease, but emerging data suggest that altered vitamin D homeostasis may play a role in the development of type 2 diabetes mellitus (T2DM), dyslipidemia hypertension, and other cardiovascular diseases (CVD). The aim of this study was to investigate the prevalence of vitamin D deficiency in patients with T2DM with/without CVD, to correlate it with anthropometric and metabolic parameters and to determine the predictors of vitamin D deficiency. Methods. A total of 88 patients with T2DM (49 male/39 female, aged 61.0 ± 0.9 yrs, body mass index (BMI) 29.9 ± 0.4 kg/m2) and 67 patients (44 male/23 female, aged 63.6 ± 1.0 yrs, BMI 29.2 ± 0.5 kg/m2) with T2DM and CVD (myocardial infarction in 57 patients and angina pectoris in 10 patients) were included in this study. These patients were compared with 87 healthy subjects (35 male/52 female, aged 52.8 ± 1.4 yrs, BMI 27.2 ± 0.5 kg/m2). Weight, height, waist circumference and BMI were recorded in all patients. Also, total cholesterol, triglycerides, hemoglobin A1c (HbA1c) and 25-hydroxy-vitamin D [25(OH)D] levels were measured in all. According to 25(OH)D level, all subjects were divided into three categories: severe vitamin D deficiency (≤ 15 ng/mL), vitamin D insufficiency (15-20 ng/mL) and vitamin D sufficiency (20 ng/mL). We correlated vitamin D levels with anthropometric and metabolic status and determined the predictors of vitamin D deficiency. Results. Severe vitamin D deficiency was registered in 16.1% healthy subjects, in 21.6% patients with T2DM and in 26.9% patients with T2DM and CVD. Patients with T2DM who were vitamin D deficient had increased weight, waist circumference, cholesterol and triglyceride levels when compared with patients with T2DM who had sufficient vitamin D level. 25(OH)D levels correlated with BMI and waist circumference in all subjects, but did not correlate with metabolic parameters (lipids, HbA1c). The best predictors of vitamin D level in all subjects were weight, waist circumference and BMI. Conclusion. The high prevalence of vitamin D deficiency in patients with T2DM and particularly in patients with T2DM and CVD suggests that supplementation with vitamin D may be beneficial although there is still not sufficient evidence for recommending prescribing vitamin D.