Plasma activation is a method that takes the advantage of low temperature plasma to immobilize the bioactive materials. An active immobilized glucose oxidase membrane was obtained via plasma-initiated polymerization of acrylic acid. The obtained immobilized enzyme is very active and stable. After 100 tests, the response error of the glucose sensor is less than 5% and its linear detecting range is 0–300 ppm. A hydrophilic PP film treated by Ar or NH3 plasma was used for the preparation of the immobilized glucose oxidase membrane. The obtained immobilized enzyme is also very active and stable. After 180 tests, the response error of the glucose sensor is less than 4% and its linear detecting range is 0–300 ppm. Furthermore, SEM was used to study the mophology of the glucose oxidase membranes obtained via both methods. And ESCA was used to analyze the plasm-initiated polymerization products and the plasma-treated PP films so as to obtain the optimum conditions for the immobilization of bioactive materials.