为降低回旋行波管阴极的加热功率，采用支持筒切缝和支持筒外加热屏的阴极结构，运用ANSYS有限元软件对该结构的切缝数目和切缝深度进行优化计算，并分析切缝和加热屏对阴极发射带温度分布的影响；给出了阴极发射带温度和切缝数目、切缝深度的关系。在发射带同等温度条件下，对比优化结构和原结构的加热功率。结果表明，改进后的结构使得加热功率下降了约40%, 大大降低了阴极的加热功率，为高性能回旋行波管热阴极的研制提供了一定的参考。

To reduce the Gyro-TWT cathode heating power, the paper adopts a new cathode structure with opening slot and adding heat shield on its support cylinder. The finite element analysis software ANSYS is used to optimize the number and the depth of slot and analyze the impact of heat shield on the cathode temperature. The relationship between the temperature of cathode emitter and the depth of slot is given. With the same temperature of cathode emitter, the heating power was compared to optimized structure and original structure. The results show that the optimized structure makes the heating power decreased by about 40%, greatly reducing the cathode heating power, which provide a certain reference value for the development of high performance cathode of gyrotron traveling wave tube.