A serpentine mineral was treated in a planetary ball mill, and the effect of grinding was studied on the crystalline structure, average size, and metal extraction rate by sulfuric acid leaching. The crystalline peaks of the serpentine were gradually reduced with increase of grinding time, and after 120 min the serpentine turned into the amorphous phase. It was found that the extraction rate of the metals contained in the mineral by sulfuric acid was rapidly increased by the mechanochemical treatment. For the mineral treated for 240 min, Mg and Fe metal elements were extracted at 100% within 5 min, while 83% and 58% of Ca and Al, respectively, were obtained within 10 min.