The invention discloses a manufacturing method for a silicon-contained aluminum alloy welding wire rod for spaceflight, and relates to a manufacturing method for a welding wire rod. The manufacturingmethod aims to solve the problem that gas holes, slag inclusion and cracks easily occur in the welding process due to the fact that an existing silicon-aluminum alloy welding wire is poor in internalstructure. The manufacturing method comprises the steps of 1, carrying out smelting,2, carrying out casting, 3, carrying out saw cutting, 4, carrying out turning on an oxidation skin, 5, carrying outpreheating; 6, carrying out extruding; 7, carrying out annealing; 8, carrying out primary stretching; 9, carrying out intermediate annealing; and 10, carrying out second stretching so as to obtain thesilicon-contained aluminum alloy welding wire rod for spaceflight. The silicon-contained aluminum alloy welding wire rod manufacture through the manufacturing method has the advantages of being uniform in structure and free of coarse grains. The manufacturing method is mainly used for preparing the silicon-contained aluminum alloy welding wire rod for spaceflight.