Ni-W-Si intermetallic composite coatings with W5Si3 compound phase as the reinforcing phase were fabricated on AISI 304 stainless steel by laser alloying process using Ni-W-Si powers. The microstructure and composition of the coatings was characterized by SEM, XRD and EDS. The effect of the W、Si content on the hardness and wear resistance of coatings was investigated. Results indicate that a great deal of petaloid or cellular compound phase of W5Si3、CrSi2 and (Fe, Ni) solid solution were found after laser alloying process. Unmelted W particles were found particularly in the coatings with high proportion of tungsten. New alloy phase nucleated and grown into petaloid structure around W. The wear mechanism was mainly abrasive wear. Attributed to the high hardness and toughness of W5Si3, coatings had high hardness (the highest being 1040HV) and the wear resistance was elevated to 4~8 times higher.