Synthesis and chemical oxidative polymerization of some N-substituted pyrroles ((N-Py)s) were carried out using Clauson-Kaas method and FeCl3 in CHCl3 medium, respectively. The produced polymers, N-(p-benzoic acid)polypyrrole (NpbPPy); N-(o-aminophenyl)polypyrrole (NoaPPy); N-(m-nitrophenyl) polypyrrole (NmnPPy), were characterized by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) analysis. An enzymatic glucose biosensor is fabricated through immobilizing glucose oxidase (GOX) into N-substitued polypyrrole matrixes. The parameters affecting the fabrication and experimental conditions of biosensors were optimized. The best biosensor results were obtained for NpbPPy matrix. The sensitivity of the proposed biosensor permitted the determination of glucose in the concentration range of 0-9.2 M with a detection limit of 1x 10- 6. The apparent Michaelis-Menten constant (KMapp) for the sensor was found to be 25.95 mM.