Objectives: This study aimed to evaluate the management of type 2 diabetes mellitus (DM) patients who apply to primary healthcare services (PHS) and tertiary healthcare services (THS). Methods: This is a cross-sectional study that used information about patients diagnosed with DM for at least 1 year from 25 family health centers considered PHS and Health Application and Research Hospital Endocrinology and Internal Diseases Polyclinics considered THS. A questionnaire including sociodemographic characteristics, DM-related features, and laboratory parameters was applied to the DM patients. Results: This study included 979 patients with DM: 515 (52.6%) patients from THS, and 464 (47.4%) from PHS. The HbA1c value was measured in 509 (98.8%) of the patients who were followed up in THS and 449 (96.8%) of the patients who were followed up in PHS (p=0.026). It was determined that 68 (13.2%) of the patients in the THS and 61 (13.1%) of the patients in the PHS had a history of cardiovascular disease (p=0.979). Hypoglycemia was detected in 66 (12.8%) of DM patients managed in THS and 34 (7.3%) of DM patients managed in PHS (p=0.005). There was no difference between PHS and THS in terms of diabetic retinopathy, diabetic nephropathy, and diabetic neuropathy (p=0.098, p=0.100 and p=0.073, respectively). Conclusion: DM is a chronic metabolic disease that requires continuous medical care, and the role of PHS in DM management needs to be increased.