We investigate the spectra of the gain and pump-to-signal relative intensity noise (RIN) transfer in silicon optical parametric amplifier (SOPA) with Raman effect, and draw a conclusion that Raman effect makes the spectra narrower from 260 nm to 180 nm. A maximum gain also appears at 1622 nm. Moreover, the effects of the related parameters in SOPA on the gain and the pump-to-signal RIN transfer characteristics are also discussed. The high gain (16 dB) and low pump-to-signal RIN transfer (7 dB) can be obtained by using the appropriate parameters of pump and silicon waveguide.