In this study, Al₂O₃-TiB₂ coating was successfully deposited on steel substrates by in situ plasma spraying (IPS) using H₃BO₃, Al, and TiO₂ reactants. Beside TiB₂ and Al₂O₃, Al₁₈B₄O₃₃ was formed as a by-product with ratio of about 13 wt%. The effect of milling time of reactant and the reaction behavior was also explored. Milling process for at least 10 h can promote efficiency of reaction and milling for efficient production of Al₂O₃-TiB₂ composite. Wear behavior was examined in terms of hardness, wear track width, and wear rate of the coatings with respective measured values of 797.6 HV, 1061.3 µm, and 4.2 × 10⁻³ mm³/N.m. Based on the FESEM observations, the thickness of abrasive coating was 417 µm, delamination and adhesion were the main wear mechanisms in Al₂O₃-TiB₂-coated specimens.