<p>NiTi alloys with varying La₂O₃ concentrations (0, 0.05, 0.10, and 0.15%) were fabricated using selective laser melting (SLM). The effects of La₂O₃ content on the microstructure, phase transformation behavior, and friction and wear properties of SLM-NiTi alloys were investigated by X-ray diffraction, differential scanning calorimetry, scanning electron microscopy, microhardness testing, tensile testing, and friction and wear testing. The results show that the addition of La₂O₃ enhances the fluidity of the molten pool. Specifically, when the La₂O₃ content is 0.05%, the metallurgical bonding performance is optimal, the grains in the molten pool are more refined, and the microhardness value reaches a maximum value of 395.3 HV. With the increase of La₂O₃ content, the phase transformation temperature first increases and then decreases. It is worth noting that when the La₂O₃ content exceeds 0.10%, the reverse martensitic phase transformation is promoted. When the La₂O₃ content is 0.05%, the width and depth of the wear scar are the smallest, the amount of wear debris on the wear surface is reduced, and no obvious plastic deformation is observed, which indicates that both abrasive wear and adhesive wear effects are reduced, and there is only slight oxidation wear, thus showing the best wear resistance.</p>