The response of UWB signal acting on the coating radar absorbìng maferial (RAM) targets have been investigated experimentally by time-domain method and frequency-domain method in this paper. It is shown that the UWB signal is 10～12dB superior to the narrowband signal of conventional radar for anti-coating RAM'S targets，and it has been clearly indicated that UWB signal has indeed good capabilities for mitigation of effects of RAM.