The spin valve [NiFe/Cu/Co/Cu]N multilayers were prepared by using electr on bean method. The influences of thickness on the magnetoresistance (MR) werestudied. We also investigated the stability of MR and tried to reduce the center field H0, which is the center magnetic field of the linear region in the MRH curve. Under optimum seeking conditions, we have deposited many samples with low center field H0 in range of (10—20)(103/4π)Am-1,the merit is larger than 0.2%×((103/4π)Am-1)-1. The variation of MR in the linear region in the MRH curve is reversible during repeatedly magnetizing. After annealed at 200℃ for 15 minutes, MR increased and Hrm reduced with a small amount. The change of MR is less than 0.3% for several samples after aging one year in the dry air chamber and room temperature.