<p>This review paper of the dispersion compensations techniques for the optical fiber communication system. In optical fiber communications systems there two important dispersions compensations systems are dispersion compensation fiber DCF and fiber Bragg grating FBG. These two techniques are the most significant techniques to resolve the problem of dispersion phenomena. during this research the properties of those two techniques are characterized depending on the most important factors BER, Q factor and the transmission distance. In our work the simulation will be performed to transmit eight high speed channels during optical fiber line using an optical Opti system software. In addition the comparison between NRZ and RZ modulation formats will be performed at 2.5 Gb/s in terms of Q factor and BER and transmission distance using two compensation techniques according to the position of the optical fiber, pre-compensation techniques.</p>