With the development of high power semiconductor pump technology and new fiber structures, high power fiber Raman lasers become a research focus nowadays. Starting with models of silicon germanium single-clad fiber Raman laser, double-clad fiber Raman laser and photonic crystal fiber Raman laser, the basic theories of high power fiber Raman lasers are introduced, the merits and defects of them are reviewed, and the latest developments are reported. The developments in the narrow linewidth fiber Raman amplifiers are advanced, and the technological difficulties and solution methods are discussed. Finally, the prospects of high power Raman technology in high power fiber Raman lasers are predicted.