Three kinds of laser boronizing composite coatings were in situ synthesized on Ti substrate by using powders of B, BN and B 4 C as starting materials. Microstructures of the laser boronizing composite coatings were investigated by means of X-ray diffraction (XRD), scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM); and their worn surface morphologies were also observed by using SEM. Moreover, the friction and wear behavior of the boronizing composite coatings under dry sliding condition were evaluated using a UMT-2MT friction and wear tester. It was found that all the three types of laser boronizing composite coatings had higher microhardness and better wear resistance than pure Ti substrate; and their microstructure and wear resistance varied with varying pre-placed powders of B, BN, and B 4 C. Under the same dry sliding test conditions, the wear resistance of the three kinds of laser boronizing composite coatings, i.e., sample 1 prepared from pre-placed B, sample 2 obtained from pre-placed BN, and sample 3 fabricated from pre-placed B 4 C, is ranked in an order of sample 1>sample 2>sample 3, which, surprisingly, well conforms to their order of hardness and friction coefficients.