The invention discloses an aluminum-zinc-tin system sacrificial anode material and a preparation method thereof, wherein the material comprises the following components in percentage by weight: 5.0-8.0% of Zn, 0.05-0.2% of Sn, 0.01-0.05% of Ga, and the other is Al. Compared with an existing AlZn-Sn anode material, the aluminum-zinc-tin system sacrificial anode material briefly has the advantages that firstly, the aluminum-zinc-tin system sacrificial anode material of the invention has good activation performance, and reaches the reasonable range -1.0-1.1V(SCE) of protection potential, secondly, a minute quantity of Ga, Ga and Sn are added into the aluminum-zinc-tin system sacrificial anode material and are dissolved in solution in an ion state, tin ions are firstly restored to the original state, and deposit on the surface of an aluminum anode, and gallium ions also deposit on the deposited tin, thereby a Ga-Sn alloy active point with good flowing performance is continuously formed on the surface, oxidation film is partly separated, the aluminum anode has higher electric current efficiency and uniform surface dissolve performance, thirdly, the current efficiency of the aluminum-zinc-tin system sacrificial anode material of the invention can reach above 93% through micro-alloying, and the actual capacitance quantity reaches above 2620A.h.kg-1.