The present invention relates to an image processing system for enhancing the image quality of an ultrasound image. The image processing system may include: an image data forming unit for forming image data based on image signals acquired from a target object; a log-compression unit for log-compressing the image data to provide a log-compressed image; a TGC processor for analyzing a vertical profile of pixel intensities in the log-compressed image and automatically setting a TGC (time gain compensation) parameter based on the analysis result; a gain processor for calculating mean brightness of pixels included in the log-compressed image applying the set TGC parameter and comparing the calculated mean brightness with predetermined brightness, thereby automatically setting a gain parameter based on a comparison result; a DR processor for automatically setting a DR (dynamic range) parameter by using edge contrast and background roughness of the log-compressed image applying the set TGC and gain parameters; and an image forming unit for applying the TGC, gain and DR parameters to the image data.