To study the effects of different grinding parameters, different mass fraction and sizes of Cr₃C₂ on ground surface quality of the laser cladding Cr₃C₂/Ni based composite coating, as well as to explore the grinding characteristics and the generation mechanism of the ground surface defects, the grinding experiment was conducted by using CBN grinding wheel, and the results show that the defects on the ground surface of laser cladding Cr₃C₂/Ni based composite coating mainly include two categories: one is generated in the Ni based alloy which includes debris adherence, grinding traces, micro-crack and cracks; the other is the broken Cr₃C₂ particles and voids generated by the pullout of the broken Cr₃C₂. The debris adherence in the Ni based alloy is easier to form under the condition of smaller depth of cut and lower Cr₃C2 mass fraction in the coating. As the cutting depth increases, deeper grinding marks and micro-crack appear. The cracks form in the Ni based alloy when the mass fraction of Cr₃C₂ in the coating is higher than 20%. More voids are found on the ground surface when the mass fraction of Cr₃C₂ is 30%. Under the same grinding parameters, the Ra value of ground coating increases with the increase of the size of Cr₃C₂ particles and decreases with the increase of mass fraction of Cr₃C₂. However, the Ra value increases slightly when the mass fraction of Cr₃C₂ exceeds 20%. The experimental results reveal that there are fewer defects on the ground surface when the size of Cr₃C₂ is smaller and the wheel speed is higher.