Abstract: In order to adapt the technical requirement of the cathode for the minitype pulse TWT used in carry-man spaceflight for low operation temperature, large emission current, good cathode activity and high reliability, a new type of reservoir oxide cathode is discussed in this paper, which includes the development of a Ni-Re-Ir sponge diffusion layer on the Ni net surface and a new Ti powder reservoir emission material. The results show that the new cathode have good emission performance which used in minitype pulse TWT providing 5～6A/cm2 emission current with 8～10μs pulse width and 1% duty cycle at 800℃ and 1000h lifetime. Furthermore, the cathode turn-on time is reduced to 30 second with 3.6 W heating power by improved the cathode structure and the knighthead material. And the improved cathode has successfully been used in some spy satellite TWT.