High Peak to Average Power Ratio (PAPR) reduction is still an important challenge in Orthogonal Frequency Division Multiplexing (OFDM) systems. In this paper, we propose a novel Zadoff-Chu matrix Transform (ZCT) precoding based Selected Mapping (SLM) technique for PAPR reduction in OFDM systems. This technique is based on precoding the constellation symbols with ZCT precoder after the multiplication of phase rotation factor and before the Inverse Fast Fourier Transform (IFFT) in the SLM based OFDM (SLMOFDM) Systems. Computer simulation results show that, the proposed technique can reduce PAPR up to 5.2 dB for N=64 (System subcarriers) and V=16 (Dissimilar phase sequences), at clip rate of 10-3. Additionally, ZCT based SLM-OFDM (ZCT-SLM-OFDM) systems also take advantage of frequency variations of the communication channel and can also offer substantial performance gain in fading multipath channels. © School of Engineering, Taylor's University.