The difference of organization in different location of the ZTC4 electron beam welding joint was discussed through the microscopic hardness test, metallographic analysis and conventional mechanical property test. The correlation between microscopic hardness and microstructure of EBW joint and the tensile and impact performance of EBW joint were also studied. Study found that the microstructure of ZTC4 EB weld changed from original β to acicular α’, and the microstructure of HAZ was composed of a mixture of flaky α and original β. The microscopic hardness of EBW joint was higher than base metal and HAZ, and tensile and impact performance of EBW joint were equivalent to the base metal. By studying the difference of performance characteristics between ZTC4 EBW joint and base metal, the foundation of research was provided for ZTC4 EBW application, and the wider and wider application in aerospace industry was promoted for large-scale titanium alloy casting and welding structure.