All reactive metals and their alloys, during welding process, are subjected to contamination by the gases present in the atmosphere which affects the strength, elasticity and corrosion resistance behavior of the weld. Although the use of shielded electrodes and inert gas surrounding during welding could reduce the difficulty of welding to a great extent, still the quality of the weld is not suitable as far as the nuclear and aerospace applications are concern. Electron beam has been recognized as a versatile tool for welding of reactive materials as the process is carried out under high vacuum, which is being considered to be the best inert environment. A number of reactive materials have been welded by electron beam in BARC and elsewhere for aerospace, accelerator, nuclear and defense applications. A brief description of the EB welding process for some of the above materials will be given in this paper with a discussion about their post weld mechanical properties and corrosion resistance behavior.