Modern and future optical networks rely on wavelength divisional multiplexing technology, it was necessary to developed the whole network elements to keep up with the increasing need to offer a wide band and a very short time delay and high reliability, and replacement of electro optic equipment with optical equipment. Optical amplifiers have taken an important part in this evolution, and the Raman amplifier (RAMAN) had a great deal of attention, for its high gain and flattened gain. In this paper, we have examined the effect of both fiber parameters and pump parameters on the performance of Raman optical amplifier in terms of gain and bandwidth and the used pump power. This research demonstrated the effect of multi pump on this amplifier performance and its flattening and bandwidth, and we reached a flattening gain on a wide bandwidth. The simulation was done by using MATLAB and OPTISYSTEM program based on the mathematical equations that describe the amplifier model for 1450nm-1650nm bandwidth.