Power conversion equipment is known to generate common-mode conducted disturbance. The authors have studied about common-mode apparent power evaluation, which have magnitude and phase information of the disturbance, for clarifying the generating mechanism of the disturbance. This paper describes the importance of evaluation of active power, a part of apparent power of common-mode conducted disturbance, and the validation of the active power evaluation. Additionally, verification of the active power evaluation with using DC-DC converter as EUT has been considered. As a result, validation of evaluation result has been proved by comparing common-mode apparent power, calculated from active power and measured common-mode apparent power.