Abstract: It is first time that the WC gradient hardfacing with engineering thickness on the surface A3 steel matrix was made by means of synchronously sending powder through the same outlet with laser.The laser gun which has an ability of continuously and gradiently hardfacing was developed,and the characteristic,change of rigidity and control of fusion depth of the gradient hardfacing matrix were analyzed.The resnlts showed that control the process of fine sending powder can control the fusion depth and component of interface.A gradient change of the powder component can make the rigidity of the hardfacing,abrasion properties and granularity of WC grain change gradiently,and can hardfacing mainly consist of the WC grain.