Apparatus and method for estimating channel in orthogonal frequency division multiplexing system

An apparatus and a method for estimating a channel in an OFDM(Orthogonal Frequency Division Multiplexing) system are provided to improve performance by using a linear interpolation method in a high fading channel and using a IIR filtering method in a low facing channel. A reception apparatus of an OFDM system includes a pilot channel estimator(309), a channel compensator(311), and a decoder(313). The pilot channel estimator estimates a channel corresponding to a pilot of a received signal and estimates a data channel by performing a linear interpolation process and an IIR filtering process on the basis of a channel-estimated value of the pilot. A decoder decodes the compensated channel signal in order to obtain an original signal. The channel estimator includes a buffer for storing the received data, an LS estimator for performing an LS(Least Squares) estimation process for the data stored in the buffer, an FI(Frequency linear Interpolation) processor for processing a frequency linear interpolation process, and a IIR filtering processor for processing each sub-carrier in a IIR filtering manner.