The invention provides a two-channel phase jitter inhibiting device and a method for a Raman laser system. The device comprises a frequency stabilized laser, a 1 / 2 wave piece, a polarization splitting prism, a 45 degrees reflecting mirror, an electrooptical modulator, a Fabry-Perot interferometer, an acousto-optic modulator, a plano-convex lens, a 1 / 4 wave piece, a 0 degree reflecting mirror, a PZT, a polarizer, a pretreatment circuit, a control circuit based on FPGA, a D / A converter, a acousto-optic modulator driver, a PZT driver, an electrooptical modulator driver and a Fabry-Perot interferometer controller. The two-channel phase jitter inhibiting device and the method can realize the independent control of power and frequency of two lasers; a high-frequency feedback and a low-frequency feedback are utilized to inhibit the phase jitter of the Raman laser; compared with a single-channel phase feedback system, the requirement on the circuit system is reduced, and the stability of the phase feedback system is improved.