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The corrosion and high-temperature oxidation characteristics of AM60 magnesium alloys in different environments were investigated by means of immersion test，electrochemical polarizing analysis and DTA/TG experiments. The influence of aging heat treatment on the corrosion resistance of AM60 magnesium alloys has been studied in details. It showed better corrosion resistance in sea water than in 3.5wt％ NaCl solution. The corrosion resistance after aging 24h was better than that of both as-cast and aging 48h ones. Corrosion resistance of Mg Alloy is controlled by microstructure，composition of αmatrix. Precipitation of βphase along the grain boundaries acts as a barrier which decrease corrosion rate，while the decrease of aluminum content of α causing an increase in the corrosion rate. The DTA and TG curves of heating process in air are characterized with combustion after 590℃. While heating in helium，the curves show two endothermal peaks and a remarkable evaporation of magnesium. Are different each other for AM60 heated in air and helium atmosphere. As for isothermal DTA and TG experiment，weight increment does happen till 520℃ which results from oxidation.