A hybrid technique integrating wire arc additive manufacturing and high-speed milling of Al5Si alloy was carried out. It was found that the milling made the layered structure characteristics more obvious. After the surface was milled to a plane, it helps to stabilize the next arc combustion and concentrate the arc heat distribution on the deposited surface well, so the area of bonding zone increased. Secondly, the fusion line spacing was reduced under the milling. So the fusion line was parallel and densely distributed in the vertical direction, which had a certain influence on the tensile properties. The tensile test results showed that the ultimate tensile strength (UTS) gradually becomes larger in the horizontal direction, but decreases in the vertical direction when the t increases. Relatively, the UTS in the vertical direction are smaller than those of the horizontal direction, and the difference of the UTS increases linearly with the t.