The gyrotron is one of the important high-power microwave sources, but it has the capability to output continuous-wave power or continuous-pulse power. Therefore, this chapter specifically introduces the power measurement of continuous-wave and continuous-pulse-wave high-power microwaves, including dry and liquid calorimetric power meters, thermoelectric power meters, thermocouple power meters, ferrite power meters, detector power meters, and other electromagnetic effect power meters. It also covers methods for measuring continuous-wave power, such as average power method, peak detection method, comparative measurement method, notch method, etc., and introduces their measurement principles, power meter composition, and measurement methods.