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Ni75Fe25-SiO2 granular films are fabricated and studied for high frequency applications. The films of different metal volume fraction fv are fabricated by magnetron co-sputtering and they have fcc Ni3Fe structure determined by X-ray diffraction. Magnetic hysteresis loops show that the samples of fv=0.81 have in plane uniaxial anisotropy. The resistivity ρ is shown to increase slowly with decreasing fv then increases rapidly after fv>0.7, while coercivity Hc decreases rapidly as fv decreases from 0.81 to 0.52 and does not exceed 5 Oe. In this fv range, good soft magnetic properties are obtained especially for the sample with fv=0.52 in which ρ reaches 19000 μΩ·cm with negative temperature coefficient. This high ρ effectively depresses the eddy current loss as applying for high frequency range. These interesting behavior is understood by exchange coupling between nanoparticles.