© 2016, Scientific Publishers of India. All rights reserved.Aim: The aim of this study was to compare the levels of 25(OH) Vitamin D in patients of type 2 diabetes, taking oral antidiabetics (OAD) medication and insulin. Materials and Methods: This study is based on data collected at the time of admission from 126 patients of type 2 diabetes mellitus (DM) and 62 healthy patients in the control group, who were admitted to the Policlinic of Endocrinology in the Department of Internal Medicine and Policlinic of Family Medicine in the Education and Research Hospital of Faculty of Medicine, Eskişehir Osmangazi University between October 1, 2013 and April 30, 2014. For the purpose of this study, HbA1C, lipid profile and 25(OH) Vitamin D levels of the patients were determined simultaneously. Results: 25(OH) Vitamin D levels of participants in the control group (22.371 ± 13.888) were higher than the levels of patients in the OAD group. 25(OH) Vitamin D levels of participants in the control group (22.371 ± 13.888) were also higher than the levels of patients in the insulin group (10.177 ± 6.188). The level of 25(OH) Vitamin D was higher in the OAD group; however, the difference was not significant (p=0.189). Discussion: 25(OH) Vitamin D levels of the insulin taking group were lower than the OAD taking and control group because of the increase in insulin resistance. Considering that diabetes plays a role in organ damage and dysfunction, the cost-effective and easy treatment of Vitamin D becomes more important.