The invention discloses a glue pouring clamp of a travelling wave tube electron gun. The glue pouring clamp is an n-shaped container and further comprises a diversion container, a through hole is arranged in the side surface, which is close to the bottom end of the electron gun, of the diversion container, when the diversion container and the n-shaped container are fixedly connected, the bottom end of the diversion container maintains level with the bottom end of the n-shaped container, the height of the diversion container is greater than that of the n-shaped container, and a through hole communicating with the through hole of the diversion container is arranged in the side surface, which is close to the bottom end of the electron gun and is in contact with the diversion container, of the n-shaped container. By using the glue pouring clamp and the glue pouring method, secondary bubble discharge processing is unnecessary, and thus the labor, time and energy cost is reduced; change of the magnetic field value of a magnet ring, result from change of the temperature of the rare earth magnet ring, caused by affected heat conduction of a travelling wave tube due to silicone rubber mingled in the gap between the travelling wave tube and a base plate, is prevented; and the situation where dynamic parameters of the travelling wave tube are changed in a silicon rubber removing process is avoided.