As technology advances, the image display technology and industry have been evolved as well. In the research field of color images, image quality analysis and enhancement are increasingly important. Therefore, we focus on image enhancement in this research. For this reason, we propose a new opinion about image enhancement by multi-scale image filter. The multi-scale image filter apply the bilateral filtering scheme and PSO algorithm to improve the image quality. This study expects to improve the image quality by multi-scale image filter.