Three kinds of stabilized rapid-heating, quenching and transformation annealing (RHQT) Nb 3 Al round wires have been developed for nuclear fusion devices; the Ag internally stabilized Nb matrix, the Cu internally stabilized Ta matrix and Cu ion-plated/electroplated wires. The critical current densities J c of Nb 3 Al filaments are almost the same as the conventional Cu clad stabilized flat-wire, as long as the J c is optimized by mechanical deformation of wire after quenching but before the final transformation annealing. To demonstrate the applicability of RHQT Nb 3 Al wire to nuclear fusion devices, we have trial manufactured a cable-in-conduit conductor (CICC) using the Ag internally stabilized round strands and confirmed the critical current of CICC to be nearly the same with the strain-free designed one.