To provide a ceramic roller which consists of a sialon sintered compact and has excellent wear resistance.

This ceramic roller consists of the sialon sintered compact composed of sialon particles and grain boundary phase. The total amt. of the grain boundary phase of the sialon sintered compact is ≤20wt.% and the Si, Al and Y converted to the oxides of the grain boundary phase exist within the limited regions of a triangular diagram (expressed by weight %) indicting the ternary component system of SiO2-Al2O3-Y2O3. The porosity is ≤10%, the crystal grain size is ≤20μm and the surface roughness is 0.1 to 10μm. The fracture toughness value is ≥5.0MPa.m1/2 and the Vickers hardness at 800°C is ≥800.