BACKGROUND Millions of Muslims fast from dawn until dusk during the annual Islamic holy month of Ramadan. Most of the studies evaluating biochemical changes in diabetic patients during Ramadan showed little changes in the glycemic control. In this study, our aim was to assess the impact of fasting during Ramadan on glycemic control in patients with type 2 diabetes. METHODS We examined 122 patients with type 2 diabetes (82 female, 40 male, age 56.93 ± 9.57 years) before and after the Ramadan. 66.4% of the patients were treated with oral antidiabetic (OAD) alone, 6.5% with a combination of insulin plus OAD and 19.7% with insulin alone. 88 of 122 patients fasted during Ramadan (26.98 ± 5.93 days). Weight, body mass index (BMI), waist circumference, blood pressure, fasting plasma glucose (FPG), postprandial glucose (PPG), fructosamine, HbA1c, fasting insulin and lipid parameters were measured. RESULTS The frequencies of both severe hyperglycemia and hypoglycemia were higher in the fasting group, but the difference was not significant (p=0.18). Weight, BMI, waist circumference, blood pressure, FPG (143.38 ± 52.04 vs. 139.31 ± 43.47 mg/dl) PPG (213.40 ± 98.56 vs. 215.66+109.31 mg/dl), fructosamine (314.18 ± 75.40 vs. 314.49 ± 68.36 µmol/l), HbA1c (6.33 ± 0.98 vs. 6.22 ± 0.92%) and fasting insulin (12.61 ± 8.94 vs. 10.51 ± 6.26 µU/ml) were unchanged in patients who fasted during Ramadan. Microalbuminuria significantly decreased during Ramadan (132.85 ± 197.11 vs. 45.03 ± 73.11 mg/dl). CONCLUSIONS In this study, we concluded that fasting during Ramadan did not worsen the glycemic control of patients with type 2 diabetes.