The use of optical frequency domain phase conjugation (FDPC) to suppress pulse impairments due to cross-phase modulation (XPM) in optical fiber systems is proposed. Evolution of Gaussian pulses in the system using midway FDPC is analyzed theoretically and simulated numerically. It is found that pulse waveform impairments induced by XPM can be suppressed effectively by FDPC. The impairments due to group-velocity dispersion and self-phase modulation can be suppressed simultaneously. Suitable initial time delay and pulse chirp of pulses can improve the suppression and compensation for the distortion.frequency domain phase conjugation, cross-phase modulation, group-velocity dispersion, self-phase modulation can be suppressed simultaneously. Suitable initial time delay and pulse chirp of pulses can improve the suppression and compensation for the distortion.