Pulse compression experiment was conduc-ted by studying the clamping effect of stokes pulses in SRS of short optical fiber (L≈Lw) on pulse energy of fundamental wave. With the high pumping power (P = 1600W) injecting into a 8.95m long monomode optical fiber for green light, moda-looked and frequency doubled NdrYAG laser pulse of 40 ps was compressed to have the duration of less than 5ps (due to the limitation of temporal resolution of the streak camera), by employing the configuration of a pair of grating with double optical path length, and filtering out the portion of nonlinear chirp of SPM spectrum with the spatial frequency window.