Diabetes mellitus is a massive, growing, silent epidemic that has the potential to cripple health services in all parts of the world. Currently, a diagnosis of diabetes is achieved by evaluating plasma glucose levels. Saliva offers some distinctive advantages. Whole saliva can be collected non-invasively and by individuals with limited training. The present study was aimed to estimate and correlate the plasma and salivary glucose levels in diabetic and non diabetic subjects, with special reference to age.