Abstract As a Radar Countermeasure technique, Active cancellation could further decrease the radar detection probability of a stealthy target in some interest directions accomplishing with some traditional stealth techniques. According to radar equation, the received power of radar from the scattering of the target is positively linearly relative to the Radar Cross Section (RCS) of the target. The traditional stealth techniques aim at reducing the RCS by shaping and materials, but the active methods center the parameters of radar wave. Practically, there are many difficulties such as the real time signal measurement, the accurate anti-signal production, etc. In this paper, a type of structure of active cancellation system is proposed, and verified by measurement results its technique indexes This paper designs, and. At last, a verification experiment system and the confirm our conclusions about active cancellation stealth technology.