In the present investigation, TiC-TiB2 composite coating was deposited by electrical discharge hardening onto the surface of 40Cr steel with a TiC-TiB2 composite rod as electrode. The composite coating structure and phase compositions were characterized by SEM and XRD, the hardness and its distribution along coating were measured on micro-hardness machine. Wear resistance of composite coating was evaluated on MM-200 wear experiment machine. The results suggest that the major phases of the composite coating are TiB2, TiC and Fe3C. The micro hardness distribution along depth of composite coating is inhomogeneous, the micro hardness value of the composite coating is about 4 times of the substrate. The wear mechanism of 40Cr steel is mainly attributed to micro-cutting and adhesive wear, but the wear mechanism of composite coating is mainly attributed to micro-cutting, scratch and fatigue abrasion. The results show that the change of wear mechanism between the samples because of the hard particles and higher hardness of composite coating. Compared with the substrate, wear resistance of composite coating is 5 times higher than that of the substrate, friction coefficient of the coating decreased by 0.12-0.17 under the same wear environment. The erosion mechanism of the TiC-TiB2 composite coating is ploughing and cutting at low impact angles, but it failure in fatigue cracking and spalling at high impact angles. (C) 2016 Elsevier B.V. All rights reserved.