A magnesium alloy structural member having excellent corrosion resistance is provided. The magnesium alloy structural member includes a magnesium alloy substrate that contains more than 7.5% by mass of Al and an anticorrosive layer formed on a surface of the substrate by chemical conversion treatment. The substrate contains a precipitate, typically, particles dispersed therein. The particles are made of an intermetallic compound containing at least one of Al and Mg and have an average particle size of 0.05 μm or more and 1 μm or less. The total area of the particles accounts for 1% by area or more and 20% by area or less. The anticorrosive layer includes a lower sublayer and a surface sublayer on the substrate in this order. The surface sublayer is denser than the lower sublayer. The substrate of the magnesium alloy structural member has high corrosion resistance because of a high Al content. The magnesium alloy structural member has excellent corrosion resistance because of the dense sublayer on the front side of the anticorrosive layer, which prevents a corrosive liquid from reaching the substrate. The porous lower sublayer can reduce the tendency of the anticorrosive layer to detach from the substrate, for example, upon impact and allows the magnesium alloy structural member to retain high corrosion resistance.