The scale-transformation method make the stochastic resonance (SR) system can processing the underwater acoustic frequency, there are many factor to effect the output, this paper study on the effect factor of the SR system, the result shown that The signal can be detected from the spectrum of the output when fs is bigger than 20 times f0. If fs is less than 20 times f0, the output is not ideally, even mis convergence, Higher scale factor bring lower transition frequency at higher SNR, if the SNR is low, the output would mis convergence when higher scale factor, The system parameter a is more effect to the output than b.