Silicon nitride ceramic strips were prepared by air pressure sintering process with α-Si3N4 powder as raw material and MgO-La2O3-Lu2O3 as ternary composite sintering aids. The effects of sintering aids and β-Si3N4 on the microstructure and mechanical properties of silicon nitride ceramics were studied. The results show that the ternary composite sintering aids promote the densification of sintering and improve the mechanical properties of the materials. At the highest sintering temperature of 1 750 ℃ and the addition of 8% (mass fraction) composite sintering aids, the silicon nitride ceramics for ice skates with density of 3.172 8 g/cm3, Vickers hardness of 15.85 GPa, fracture toughness and bending strength of 9.69 MPa·m1/2 and 1 029 MPa can be obtained. The fracture toughness of the material is enhanced by adding β-Si3N4, and the maximum fracture toughness is 10.33 MPa·m1/2. The high hardness of Si3N4 ceramics itself and the addition of rare earth oxides improve the hardness and lubricating properties of the prepared ice skates, and the surface properties of ice skates are excellent.