Objective To solve the problem of high temperature erosion, thermal spray coating was prepared and studied on 350 MW supercritical unit reheated level stator cascade. Methods High velocity oxygen fuel spraying ( HVOF) was used to prepare NiCr-Cr₃C₂coating. A series of coating performance were tested, such as microstructure, porosity, micro-hardness, adhesion strength and high temperature erosion performance. And then the failure mechanism of coating in the erosion conditions was analyzed. Results Under the laboratory conditions, the coating porosity was 0 . 98 % , the value of micro-hardness HV0 . 3 was 1061 . 2 ,and the bonding strength was about 80 MPa.Under the working conditions of the stream turbine, when the thickness of coating was 0 . 22 mm, the service life of the first reheated level stator cascade was 3 times longer than the original . Conclusion The service life of stator cascade can be prolonged after using NiCr-Cr₃C₂coating. The main reason for the accelerated failure of the coating is plough erosion of small angle particles.