The stimulated Raman amplification of picosecond Stokes pulse is numerically investigated in ultra-small silicon-on- insulator optical waveguide. Numerical results show that we obtain the gain of up to 30-dB for weak Stokes pulse in the co- propagation configuration for 10 mm Jength waveguide using high intensity pump optical pulse. The peak gain, pulse width, rise time, and fall time of Stokes pulse will experience the variation course of decaying then increasing with increas- ing waveguide length. The time delay of output Stokes pulse is controlled by adjusting the initial time delay of both pump and Stokes pulses. The stimulated Raman amplification of picosecond Stokes pulse is numerically investigated in ultra-small silicon-on-insulator optical waveguide. Numerical results show that we obtain the gain of up to 30-dB for weak Stokes pulse in the co-propagation configuration for 10 mm The peak gain, pulse width, rise time, and fall time of Stokes pulse will experience the variation course of decaying then increasing with increas- ing waveguide length. The time delay of output Stokes pulse is controlled by adjusting the initial time delay of both pump and Stokes pulses.