History and Objectives: Considering the high prevalence of diabetes mellitus and the importance of controlling the biochemical indices and its side effects, the present investigation was carried out in order to assess the effect of fasting on diabetic mellitus type II on patients referred to the Diabetic Center of Kashan.

Materials and Methods: A quasi experiment on type II diabetic mellitus patients was performed. Blood glucose, cholesterol, triglyceride, weight and blood pressure was measured before and 20 days after beginning for Ramadan Holly month. Paired T-test was used to assess the results. ]

Results: 30 diabetic patients (21 female, 9 male mean age 52.83±9.5) participated in this study. Triglyceride and systolic blood pressure show significant difference during fasting whereas blood glucose, cholesterol and diastolic blood pressure did not display significant differences. Body weight did show detectable difference.

Conclusion: Fasting is not harmful for diabetic patients and it has positive effect on the control of the disease.