Abstract: In order to improve the use temperature of the hot-dip aluminized 304 stainless steel, the hot-dip coating was carried out in three ways, namely aluminizing, aluminum-plated silicon and aluminizing-aluminum-silicon（aluminized and then-aluminized silicon）. The microstructure and composition of the coating were compared and analyzed by SEM and EDS,respectively. The results show that the Al-Al-Si and Al-Al-Si can form a three-layer or even four layer complex alloy layer structure. Due to the uneven diffusion, there is a pattern-like light and dark region in the alloy layer. The addition of the Si element in the plating solution can effectively block the diffusion between the iron and aluminum. Fe element content of the surface layer is reduced, the content of the Al element is increased, and a compact oxide layer can be formed. The alloy layer formed by aluminum-silicon plating is thicker and reaches 222 μm, which is beneficial to improve the oxidation resistance of the coating at high temperature.