In this research, the kinetics study of one isoenzyme of Maltase, which purified from the urine of diabetes mellitus patients was studied. Maltase isoenzyme was obeyed Michaelis-Mentons eqution. The optimum concentration of their substrate Maltose was (300 mmol/dm 3). Their Km values was determined. Isoenzyme of Maltase have shown an optimum pH at (6.5) for phosphate buffer and (7.5) for tri ethanol amine. Maltase isoenzyme obeyed Arrhenius eqution up to 25°C and their Ea and Q 10 constant were determined, after measuring the activity of Maltase of urine of diabetes mellitus patients. Isoenzyme of Maltase was separated and purified in previous study from urine of patients of diabetes mellitus.