Granites of Yanshania,n age are widely distributed in South China, and some of them are mineralized with rare-earths, rare and radioactive elements. By applying a multivariate discrimination analysis, small differences in chemical composition of granites mineralized with niobium-tantalium, rare-earths or uranium can be distinguished in a certain degree. Different oxides in granites play different rotes in distinguishing the mineralized granites. By the discrimination function it is possible to evaluate the effect of each variable (oxide) within specimens in discriminating different mineralized granites. So the discrimination function will give discriminative values for all the specimens examined. Careful analysis of the discriminative value of each specimen shows that discriminative values can quantitatively reflect under certain conditions the minor changes in chemical evolution of granites during different intrusive periods or phases. This will help to evaluate the ore prospects of granites and the law of changes in its mineral composition.