The high speed optical network more supports for higher bandwidth and it needs choosing better optical amplifiers in long-haul fiber optic communication networks. Optical amplifiers are very helpful for long-haul transmission in fiber optic communication system. In long-haul transmission, as the power level gets high pulse broadening effects Self-Phase Modulation(SPM), Cross-Phase Modulation (XPM) and Four-Wave Mixing (FWM) may occur due to variations of the refractive index during gigabit transmission system.so it is vital to minimize the dispersion and non-linear effects using Optical amplifiers along with Dispersion Compensation Fiber(DCF) and Fiber Bragg Gratings (FBGs) to recover the original signal at the receiver end. In this thesis, the performance analysis of EDFA, RAMAN and EDFA + RAMAN at different parameters has been done on the basis of two major approaches: The first approach is fixed channel spacing where the channel spacing is fixed at 100GHz and varying Bit rate (1.25-20) Gb/s, input power (0-25) dBm and Optical fiber length (60-240) km for iterative wise. The second approach is Dynamic Channel Spacing (DCS) approach, varying channel spacing (12.5GHz - 200GHz) with constant input optical power 5dBm and optical fiber length 120km for both low bit rate and high bit rate (1.25Gb/s and 10Gb/s) by considering SPM, XPM and FWM effects. In this research analysis, EDFA has good performance than hybrid and RAMAN amplifiers for minimizing the SPM and XPM impairments and XPM affects more seriously than SPM in all Optical amplifiers. But, EDFA + RAMAN can enhance the transmission span better than EDFA and RAMAN alone. The transmission performance measured by optical signal to noise ratio(OSNR) indicates that EDFA, 94.94dB, RAMAN, 75.59dB and EDFA + RAMAN, 102.94dB. This implies that EDFA + RAMAN has OSNR improvement by 20dB than EDFA and 27dB improvement than RAMAN. This is evident that hybrid Optical amplifier works best for gain compensation and noise reduction. The complete study has supported with Opti-system for verifying various measurements, plots and all other graphical analysis.