Aim: To study correlation between salivary and serum glucose levels in diabetic and non diabetic individuals. Materials And Methods: The present cross sectional study was conducted among 100 patients of confirmed diagnosed cases of type I and type II diabetes mellitus visiting the Department Of Oral Medicine and Radiology, Vyas Dental College and Hospital and the General Hospital of Vyas Dental College, Jodhpur. The fasting blood glucose levels and the unstimulated salivary samples were collected in study and control groups. Results: Salivary glucose level was found to be significantly more among subjects suffering from diabetics (18.43±4.30 mg/dl) than non diabetics (7.09±2.37 mg/dl). Similarly, Serum glucose level was found to be significantly more among subjects suffering from diabetics (170.89±61.36 mg/dl) than non diabetics (107.10±16.28 mg/dl). There was strong positive correlation between serum and salivary glucose in case and control group. Conclusion: Our result emphatically shows the positive statistical co-relation between the salivary glucose and the serum glucose thus, assessment of the salivary glucose can be established as a non-invasive tool for diagnosis and monitoring the diabetes mellitus. Thus it can be inferred that saliva can be used as an alternative to blood for diagnosing and monitoring diabetes mellitus status as it is noninvasive compared to other fluids and can be easily used in children, elderly, critically ill and debilitated patients.