The invention belongs to an enhancement device, and particularly relates to a cathode electron enhancement device. The cathode electron enhancement device is composed of a power supply, a cathode electron emission source and a metal sheet group, wherein the metal sheet group is arranged at the electron emission end of the cathode electron emission source, the metal sheet group is composed of a plurality of long strip-shaped metal sheets, and the cross section of the metal sheet group is in a zigzag shape. The cathode electron enhancement device has the remarkable effects that the electrons emitted from the cathode are accelerated by the metal sheet group with injection of cesium, magnesium and the like under the action of a certain voltage to impact the surface of the metal sheet group togenerate secondary electron emission so as to realize electron multiplication and realize enhancement of the cathode electron emission current. Meanwhile, the shape of the metal sheet group can be adjusted, the emission electrons of the cathode electron emission source can be regulated and the electron optical effect such as focusing can be realized.