The invention discloses a method for preparing a shape memory alloy intravascular stent based on the automatic powder laying laser combination machining technology. The method comprises the steps that according to a three-dimensional data model of a part to be machined, a high-energy laser beam melting and mixing powder system is utilized, the manner of laying powder layer by layer and carrying out fusing overlaying accumulation layer by layer is carried out until a intravascular stent blank of a mesh structure is formed finally, and then electrochemical polishing is carried out to reach the specific surface roughness requirement. The intravascular stent prepared through the method is based on the unique superelasticity function and the shape memory effect of shape memory alloy, and the occurrence rate of vascular restenosis of the intravascular stent in clinical application can be effectively reduced; by means of mechanical performance and living body environment simulation tests, the intravascular stent has the good biological tissue and blood compatibility and meets the medical application condition; furthermore, based on the advantage of superhigh manufacturing precision of the laser combination machining technology and protection of inert gas in the forming process, the problems of surface roughness, burr, oxidation and the like of a traditional intravascular stent in the preparing process are effectively solved.