A magnesium alloy containing Al, Sr, Ca, and Mn, with the balance being Mg and inevitable impurities, the magnesium alloy having: a structure having an α-Mg phase, and a precipitate dispersed in at least one of a grain boundary of the α-Mg phase and a cell boundary, the precipitate including: at least one phase selected from a group A consisting of an Al2Sr phase, an Al4Sr phase, a (Mg, Al)2Sr phase, and a (Mg, Al)4Sr phase; and at least one phase selected from a group B consisting of an Al2Ca phase and a (Mg, Al)2Ca phase, the magnesium alloy having, in a cross section, a total area rate of a group A precipitate and a group B precipitate of greater than or equal to 2.5% and less than or equal to 30%.