Diagnostic membranes by using multi-layered gelatin films were prepared to measure blood glucose level of diabetics. Maximum diffusion rates through multi-layered gelatin film were measured at various concentration of glucose in plasma or blood. The effects of storage temperatures on the diffusion rates of glucose were studied after storage of 3 days, 2 weeks and 4 weeks at various temperatures. The stabilities of diagonostic membranes with multi-layered gelation films were examined at RH 80%.