To estimate the prevalence of vitamin D -deficiency among patients with type 2 DM, and to determine if there is any correlation between vitamin D -deficiency and number of independent variables. Serum 25(OH) D was measured in a cross-sectional sample of 625 cases among which 383 were with type 2 DM. Fasting plasma glucose, insulin, HbA1c, calcium, phosphorous, Parathyroid hormones, and BMI were measured. Most diabetic patients in our study were obese (76%) with a mean BMI (SD) 33.6(5.54) Kg/m2, Also 43.6% of them had diabetes for more than 5 years. According to non-diabetic subjects, there were 242 volunteers. Most of them were obese (53%) with a mean BMI (SD) 30.85(5.37) Kg/m2.However, concerning sun exposure around 84.9 diabetic vs. 86.0 non-diabetics didn't receive enough sun exposure, concerning their diet around 23.0 diabetic vs. 36.4 non-diabetics do not frequently take cheese in their diet, on the other hand, when it came to milk, more than 80.9 diabetic vs. 81.4 non-diabetics did not frequently drink milk. The mean of serum level of 25-OHD among diabetics and non-diabetics were (18.67 ng/ml vs19.18 ng/ml) respectively. Vitamin D deficiency is highly prevalent among Jordanians with or without type 2 diabetes. It is now clear that the need for serious national efforts to prevent vitamin D deficiency and its associated morbidity is highly recommended.