Giant tunneling magnetoresistance effect (TMR) as large as 1280% at 4.2K and 158% at 300K was observed in Zn0.41Fe2.59O4-α-Fe2O3 polycrystalline sample. The Zn0.41Fe2.59O4 grains are separated by insulating α-Fe2O3 thin layer boundaries, The pattern of nanostructure has been verified by TEM and HREM and the thickness of α-Fe2O3 boundary is about 6-7nm. The huge TMR is attributed to the high spin-polarization of Zn0.41Fe2.59O4 grains and insulating antiferromagnetic α-Fe2O3 thin layer. The ZnxFe3-xO4 ferrite is a new type half-metallic material with a huge TMR at room temperature is interesting to further study in future.