The cavitation erosion of Ti-46Ni-9Nb alloy, Ti-24Al-15Nb-1Mo alloy and 0Cr13Ni5Mo stainless steel has been investigated in tap water by using rotating disc equipment. It is shown that Ti-24Al-15Nb-1Mo alloy has the highest cavitation erosion resistance among the three tested materials and Ti-46Ni-9Nb alloy is more resistant to cavitation erosion than 0Cr13Ni5Mo stainless steel. To simulate the effect of collapse of vapor cavities or bubbles,the Rockwell hardness tester was used to exert a load on the small area of the tested materials, and the elastic deformation energy and total deformation energy in indentation were determined. The experiment results show that there is a good correlation between cavitaton erosion resistance and the ratio of elastic deformation energy to total deformation energy in indentation for the three tested materials. The higher the ratio, the better the cavitation erosion resistance.