Study about the feasibility and effect of high-energy ball milling on a specific Mg alloy under protection medium of alcohol was presented via comparing with conventional vacuum milling. More fine particles with wider powder size distribution but more irregular shape were shown from image analysis of the SEM pictures of the powder milled under alcohol. No obvious oxide was revealed from the X-ray diffraction of the two kinds of Mg alloy powders with limited milling time. And since slip induced in a preferential direction, the (002) texture was formed in the Mg alloy powders at the initial stage of alcohol milling. With deformation occurred randomly, the texture disappeared regularly. More O and Fe contaminants were introduced into the powders milled under alcohol according to the EDS analysis, for which the hot-pressed Mg alloy samples fabricated with that powders exhibited lower UTS.