Abstract: In order to investigate the effect of alloying elements Cr and C on the microstructure of high boron iron-based surfacing alloys, gas shielded surfacing technology was used to prepare different types of high-carbon ferrochromium on the surface of Q235 steel plate by adjusting the addition amount of high-carbon ferrochromium in the metal powder cored wire. The Fe-Cr-B-C surfacing alloy with high carbon and ferrochromium content was analyzed by metallographic microscope, scanning electron microscope (SEM), energy dispersive spectrometer (EDS), X-ray diffraction (XRD), and other analysis and testing methods to analyze the effects of different alloying elements Cr and C content on the microstructure and properties of the surfacing alloy. The results show that the microstructure of the surfacing alloy is martensite + network (Fe, Cr)₃(B, C), and a small amount of M₇C₃. The volume fraction of (Fe, Cr)₃(B, C) increases, the martensite in the surfacing alloy has higher hardness, the alloy element Cr can make the matrix structure solid solution strengthening, and the network carbide (Fe, Cr)₃(B, C) As a wear-resistant skeleton, it hinders the extrusion and cutting of abrasives in the process of wear, so that the wear resistance of the surfacing layer is 3-4 times higher than that of 65Mn steel, and the wear mechanism is micro-furrowing.