This paper describes a detection and localization method for high speed moving targets using a short-range ultra-wideband (UWB) impulse radar. Equivalent time sampling impulse radar with an antenna array is used to transmit ultra short-pulse and receive the signal reflected from moving targets. A time domain multi-threshold detection method is proposed to detect the useful weak signal buried in noise while eliminating clutter resulting from stationary objects. Then a time difference of arrival (TDOA) based algorithm can be used to localize high speed moving targets. Simulation results show that a reliable detection using such UWB impulse radar can be achieved.