Abstract: Al-5Ti-1B alloy was deformed by equal channel angular pressing (ECAP) with the number of pressing passes being 8 at room temperature.The X-ray diffraction,optical microscope and scanning electronic microscope were used to investigate the change of the second phases in Al-5Ti-1B alloy before and after ECAP deformation.The results indicate that the grain size of the second phase in Al-5Ti-1B alloy are obviously refined and more homogeneous.With the increase of pressing passes,the grain sizes of TiAl3 phase are refined from 20-80 μm to about 5 μm,and the grains of TiB2 phase are more homogeneous.The shearing action of hard second phase particles in matrix is one of the reasons of the grain refinement.