The effects of Raman amplification on propagation characteristics of the optical soliton are experimentally investigated by using second-harmonic generation frequency-resolved optical gating (SHG-FROG) technology. Raman amplification can compensate the fiber loss, does not change the temporal waveform and has little influence on the linear chirp of the soliton. And it can completely compensate the fiber loss when the propagation distance is smaller than effective fiber length, and can partially compensate the fiber loss when the propagation distance is larger than the effective fiber length. The fiber loss compensation of Raman amplification increases with the increase of the Raman pumping power. Experimental results show that the soliton is not sensitive to the polarization of Raman pumping source.