The FeCoCrNiBx high-entropy alloy coatings were prepared by laser cladding. The effect of boron addition on microstructure, hardness and wear resistance of FeCoCrNiBx high-entropy alloy coating were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), hardness and wear testers. The results show that with the boron addition increasing, the structure of alloys change from fcc structure to fcc structure with M3B phase precipitation, and M3B phase are mainly borides of Cr and Fe. Meanwhile, the granular and short rod-like M3B phase is precipitated in the coatings. And a blocky M3B phase forms with boron addition. Microhardness and wear resistance are significantly enhanced by the formation M3B phase. The microhardness increases from 4470 to 8480 MPa, and the wear-loss of FeCoCrNiBx high-entropy alloy coating decrease with boron addition