Deposition of electroless (EL) Ni-B-Si 3N 4 composite coating and its characteristic properties are addressed.Hydrogen evolution limits the level of incorporation of Si 3N 4 particles in the EL Ni-B matrix to 2 wt%. Incorporation Si 3N 4 particles increased the surface roughness of the matrix but did not influence its structure. The microhardness of EL Ni-B-Si 3N 4 composite coating in its as-plated condition is 632 ± 17 HV0. 1. Heat treatment at 350 and 450°C for 1 h increased its hardness. Adhesive wear is the predominant wear mechanism of EL Ni-B-Si 3N 4 composite coating. Its corrosion protective ability did not differ much with its plain counterpart. © 2012 Copyright Taylor and Francis Group, LLC.