Abstract: The cross-section appearance characteristics of Nd:YAG laser+CMT arc hybrid horizontal welding on 304 stainless steel was evaluated by the welding weld cross-sectional images.The influence of welding parameters on weld cross-section appearance in Nd: YAG laser+CMT arc hybrid horizontal welding were studied.The results indicated that there is a great influence of weld parameters on the weld cross-section shape in YAG laser+CMT arc hybrid horizontal welding.The addition of Nd: YAG laser into CMT arc welding can significantly improve the composite weld and CMT weld penetration in hybrid welded joint.By appropriate welding parameters(the small laser-wire distance, large laser power, the low welding speed, appropriate defocusing distance and low or high CMT power), the mechanical overlay of the weld pool and dislocation of the weld cross-section can be avoided, and the good weld appearance can be obtained.