An apparatus and a method for estimating a Channel Impulse Response (CIR) with respect to a location where a power of a channel exists are provided to enhance a channel estimator in a mobile communication system. The apparatus includes a CIR searcher for selecting a CIR group that is a region where a channel power exists, a CIR estimation part for estimating a CIR of the selected CIR group, and a Discrete Fourier Transform (DFT) for performing a DFT on the estimated CIR.