An image noise reduction method is provided. An image is received. A first-stage process is performed to the image to obtain a luminance information Y and a color information Cb and/or Cr corresponding to a pixel array in an YCbCr domain. A second-stage process is performed to the luminance information Y to reduce at least a luminance noise. A third-stage process is performed to the color information Cb and/or Cr to reduce at least a color noise. The luminance information Y and the color information Cb and/or Cr are then combined.