The false topographic phenomenon is a common phenomenon existing in the remote-sensing images obtained by sun-synchronous satellites, which brings great trouble to image users. In order to remove the false topographic phenomenon of the remote-sensing images，this paper put forward a method based on DEM data and IHS transformation and made a case study of the image of Guanyuan City in Sichuan Province. By low-pass filtering of the intensity image obtained by IHS transformation, the reflectivity information (IR) was extracted from the intensity image. By adding IR to shade relief image (SR), which was produced by DEM, a new intensity image (Inew) was obtained. A back IHS transformation was done to acquire corrected RGB image after replacing the old intensity image by the new intensity image (Inew). The experimental results indicate that the method can remove the false topography effectively and preserve the primary color.