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WC–Ni–Fe–Mo cemented carbides with fine properties were prepared by low pressure sintering. The effects of Mo content on the microstructure and properties of WC–Ni–Fe–Mo cemented carbides were analyzed in detail. The results show that the addition of Mo has obvious influence on WC–Ni–Fe cemented carbides. The addition of Mo can refine WC grains to a certain extent by inhibiting the dissolution and precipitation of WC grains in WC–Ni–Fe cemented carbides. With the increase of the of Mo content, the porosity of the alloys decrease gradually. The density of alloys first decreased and then increased, while the bending strength had the opposite trend. When a trace amount of Mo was added, the hardness of alloys was relatively stable, ?the bending strength increased obviously，the fracture toughness had a gradually decreased. When the addition of Mo contents further increased, the hardness and bending strength were both decreased, and the fracture toughness increased. WC–Ni–Fe–Mo cemented carbide with 0.5 wt% Mo had the optimum properties, which can comparable to those of WC–Co cemented carbides with the identical binder ratio. The maximum value of its hardness, bending strength and fracture toughness were HV 1460, 4245 MPa, 17.01 MPa·m1/2, respectively.