Abstract: Dynamic wear is common phenomenon in engineering practices. But most of theprevious studies used to be carried out in a steady loading condition,and the results would notbe accorded with what happenned in practice. Therefore,wear behavior of SiCp/2024Al com-posites has been investigated in two tests with different loadings :1)sliding wear;2)sand-blasting erosion. The results showed that in the sliding wear test with a steady load,the wearresistance of composites was remarkably better than that of the matrix alloys and increasedwith increasing volume fraction and size of SiC;on the contrary,in the erosion test with animpact load,the wear resistance of the composites was much worse than that of the matrix al-loys,and decreased with increasing volume fraction and size of SiC.