Sample noise response method used to determine subband threshold factors of contourlet transform denoising is proposed. By the method, we can obtain the convergence factor of each subband according to every subband statistical character driven by a standard Gaussian white noise. The hard threshold of every directional subband of each scale is determined by modifying the 3σ (or 4σ) rule in terms of corresponding effect factor. The post-processing can be carried out by adaptive Wiener filtering followed subband hard threshold in contourlet domain. Experimental results show that, using the denoising method proposed, for images corrupted by Gaussian white noise, the denoising results including Peak Signal-noise Ratio (PSNR) and quality of visual effect are satisfying. To calculate the convergence factors using smaller sample image can accelerate the denoising speed and reduce the requirement of the memory for the program, and the denoising results can be kept satisfied.