A stimulated Raman scattering (SRS)-based multiwavelength fiber laser comprising of broadband chirped fiber Bragg grating and Sagnac interleaver is investigated experimentally. Four-wave mixing processes among channels are introduced into the cavity through a length of dispersion-shifted fiber (DSF) with small integrating Raman gain. Results show that four-wave mixing plays a role of transferring energy from higher power channels to lower ones, and the quantity of output wavelength increases from three without DSF to six at the same pump level.