Transformation toughening and dispersion toughening are the main toughening mechanisms on zirconia. Zirconia is used as the toughening phase of laser cladding layer, and the TA15 titanium alloy is selected as substrate on which the cobalt-based composite powder (Stellite-6) with 5% (mass friction) of ZrO2 is cladded. The results indicate that zirconia can refine and purify the microstructure of the coating and improve compactness of the coating to some extent. Moreover, the cracks which appear in the coating have been repaired, the microstructure of the coating has been improved. The X-ray diffraction spectrum has proved phase structure of zirconia ceramic in the coating is monoclinic, which has indicated the appearance of transformation toughening. The microhardness and wear resistance of the coating have been improved with the addition of zirconia. This study offers some references for improving the quality of laser cladding layer.