Orthogonal Frequency Division Multiplexing (OFDM) is the promising technology for future broadband wireless communication system especially based on multicarrier modulation which make good use of available bandwidth by allocation sub-carriers. The recent interest advances in this technique is mainly due to the recent advances in digital signal processing technology. The drawbacks of high Peak to Average Power Ratio (PAPR) can outweigh all the potential benefits of Orthogonal Frequency Division Multiplexing (OFDM) signals. In this Paper, a sophisticated PAPR reduction technique, named Iterative Clipping and Filtering (ICF) with DCT/IDCT transformation, is proposed for OFDM system. By considering the example of OFDM, with Quadrature Phase-Shift Keying (QPSK) mapping, simulation results under Matlab environment show that the new proposed method performs well in reducing PAPR.