Abstract: The plasma arc additive manufacturing process was used to realize the deposition of stainless steel/high strength steel with various composite structures. The components fabricated by plasma arc have good depositional morphology and excellent mechanical properties. In order to reveal the effect of the composite structures on the macro/microstructure and mechanical properties of the components, stereo microscope, metallographic microscope, tensile and hardness testing methods were used. The results show that there are two kinds of transition interface:laminated austenite-dendrite transition and martensite transition. The microhardness fluctuation in the cross section of the components were large, which is mainly caused by the change of the structure due to the alloy elements. The various composite structures can significantly affect the properties of materials, and "stainless steel+ high strength steel"alternating structure improves the impact toughness of materials when the strength decreases little.