Obesity disrupts glucose homeostasis by metabolic disorders. Probiotics are nutritional and medicinal potential to control obesity and its related disorders. This study was aimed to investigate effects of synbiotic supplementation on weight, Body Mass Index (BMI) and blood sugar in type II diabetic patients. This clinical double-blind trial study was done on 43 (15 males and 28 females) type II diabetic patients who reffered to diabetes clinic in Sabzevar. The patients in the study were randomly divided into two groups Synbiotic and the control. The synbiotic group received 1 tablet synbiotic and placebo group received 1placebo for 8 weeks. At the beginning and end of the study, all of patients' weight and height and fasting plasma glucose levels were measured according to standard protocols. Before and after study, 24-hour dietry recall was taken and food intake and calorie consumption were calculated throughout day. Mean age and duration of disease was 54.88 ± 11.10 and 7.33 ± 5.4 years. Synbiotic supplementation leads to weight loss. BMI and blood sugar in intervention groups patients in comparison of control group. The results showed that Synbiotic supplementation reduced weight, BMI and blood glucose in type II diabetic patients and its intake can be usefull for diabetics.