In order to improve the response speed of broadband wavelength conversion technology, a tunable all-optical broadband wavelength converter based on stimulated Raman scattering (SRS) using highly nonlinear photonic crystal fiber (PCF) was designed. Based on Raman effect in optical fiber, Raman gain spectrum of photonic crystal fiber was fitted by Gaussian curve. The theoretical model of a Raman wavelength converter was established, and the effect of fiber length on conversion efficiency was discussed. The results show that 100nm conversion bandwidth is achieved under the condition of the communication system. The bandwidth is 1487nm~1587nm. Q factor changes with the wavelength of probe light and the trend of Raman gain spectrum is the same. The best wavelength conversion quality is at the maximum Raman gain coefficient. The study is of great significance to the wavelength assignment of wavelength converters and the configuration of fiber length in future optical networks.