Introduction.Diabetes is an important cause of mortality throughout the world. Type 2 diabetes mellitus (T2DM) is characterized by hyperglycemia and obesity, which are aggravated by a sedentary lifestyle. The consequences of long-term hyperglycemia include neurological or vascular complications and can lead to amputation, retinopathy, kidney failure, or other severe complications and a consequently poor quality of life. This study was conducted to report the effect of moderate exercise versus light exercise on fasting blood glucose in obese patients with T2DM. Methods. For three months, 60 patients with sedentary lifestyles aged 35 to 60 years were randomly assigned to one of two groups in this two-arm cluster randomized controlled trial. Group 1 received 30 minutes of treadmill walking at 40-60% of maximum heart rate. Group 2 was given 30 minutes of treadmill walking per day, divided into 5 minutes every 2 hours. Results. At the base line, no significant difference was found between both groups in BMI, waist to hip ratio, 6minutes' walk, fasting blood glucose and SF-36. After three months of treatment, there was no significant difference in BMI, p = 0.111, waist to hip ratio, p = 0.271, 6 minutes' walk, p = 0.614, blood glucose, p = 0.105, and SF-36, p = 0.106 between the two groups, despite the fact, that among each group significant differences for all analyzed parameters were observed. Conclusions. Repeated short walking has a similar effect on blood glucose, obesity, and quality of life as continuous long walking. Walking for 5 minutes every 2 hours may be a useful alternative for patients with T2DM.