Abstract: To explore the feasibility to test the hardness change of alloy micro area composition in partial poly area by metal micro Vickers hardness tester, based on the micro Vickers hardness test instrument for metallic materials, the method for revealing the hardness changes of titanium rich phase segregation regions in V-5Cr-5Ti alloys, which including its metallographic preparation of samples, has been established by dint of the nano-indenter and laser microscope techniques. The results showed that, after mechanical polishing, obvious hardening layer had been formed in the sample surface of V-5Cr-5Ti alloys, and the hardness of titanium rich phase segregation regions is 12 percent higher than the none segregation regions. Using the electrolytic etching method by oxalic acid aqueous solution can not only show the complete characteristics, but also effectively remove the hardening layer.