It is considered that Ti-Cr coatings can improve strength, hardness, wear resistance and corrosion resistance of base control alloys as these coatings combine the advantages of both Ti coating and Cr coating. In this study, the Ti-Cr coatings were deposited by diffusion method. The effects of deposition temperatures on the compositions and microstructures of the Ti-Cr coatings on 45# carbon steel were investigated. The coatings formed consisted of three layers. The outer layer contained Ti and Cr carbides beneath which a diffusion layer was developed. The inner layer was enriched in Ti and Cr. At low temperature (800°C) the outer layer of Ti-Cr coatings was dominated by TiC. Increasing deposition temperature led to the enhanced diffusion of Cr and a Cr7C3 and Cr23C6-dominated outer layer was identified. The growth process of Ti-Cr coating was analyzed and simulated.