Abstract: The influence of process parameters（welding current, welding speed, wire feeding speed, interlayer temperature） on the tensile strength of wire arc additive manufacturing magnesium alloy was studied, and the microstructure and properties of the deposited part under typical technological parameters were analyzed. The results show that in the parameter range of this paper, with the increase of welding current and welding speed, the strength of magnesium alloy parts increases at first and then decreases. If the welding current is too big, coarse grains are formed in the structure, while the welding speed is too fast, a large number of pores are formed. The wire feeding speed has a positive correlation with the tensile strength, the increase of wire feeding speed helps to reduce the overheat degree of the weld pool and refines the microstructure. The effect of interlayer temperature on the strength is not obvious. There are obvious differences in different areas of the deposited part. The bottom is mainly composed of coarse columnar crystal, the middle structure is equiaxed crystal structure, and the top arc area is dendrite structure. The difference of microstructure results in uneven distribution of hardness.