In this letter, we propose a novel robust impulse radio-ultra-wide band (IR-UWB) receiver design that utilizes the received UWB signal cluster sparsity characteristics to mitigate impulse noise (IN). The IN samples are easily detected and removed in the proposed receiver. Furthermore, multiple UWB signal clusters (due to multipath channel), in the proposed receiver design, reduce UWB signal blanking loss as compared with the single cluster (single path channel). The proposed receiver’s bit error rate (BER) performance is theoretically analyzed and compared with six popular existing non-linear receivers in the presence of IN over standardized IEEE 802.15.4a channel models. Unlike the existing receivers, the proposed receiver does not require a priori knowledge of the amplitude, the probability of occurrence of IN, or channel estimation.