Helium embrittlement of binary vanadium alloys has been studied using three methods of helium doping. Helium doping using the tritium trick method yields severe embrittlement at 800°C for all the alloys studied including unalloyed vanadium. th boron-10 method resulted in slight ductility loss at 800°C. Specimens doped using cyclotron implantation showed virtually no ductility loss, but some effect of helium was observed in the fractured surface. Helium release measured during tension tests has good correlation with the degree of embrittlement. These results are discussed in terms of the different state of helium clusters/bubbles as a result of different doping methods.