In order to improve the forming quality of the alloy coatings,TiB-TiC/ Co-based composite coatings was fabricated by laser cladding on Q235 steel.The effect of the processing parameter on the macro-forming of the TiB-TiC/ Co-based composite coatings was studied.The results showed that,with the increase of the thickness of the preset powder,the wettability of the cladding coatings material on the substrate surface was gradually reduced,and the dilution effect of the substrate to the cladding coatings was gradually reduced as well.With the increase of the overlap rate of the cladding coatings,the surface flatness of the cladding coatings was gradually increased,and the fusion of the overlap area was good and no obvious defects such as pores and inclusions were observed.However,the microstructure of the overlap area was obviously coarsened.With the increase of the scanning speed,the surface smoothness of the cladding coatings was decreased,and the wetting angle and dilution rate were obviously decreased accordingly.With the increase of the laser output power,the surface morphology,wetting angle and dilution rate of the cladding coatings were changing to the opposite.Based on the comprehensive analysis of the test results,good macro forms of the cladding coatings could be obtained with the process parameters of the spot size of 5 mm,the overlap rate of 50 %,the laser output power of 2.3 kW and the scanning speed of 4 mm/ s.