Abstract: An enhancement method of active faults merged with DEM,panchromatic,multispectral re-mote sensing images is proposed.Interpretation sighs of active faults are established based on spatialfeature variation of terrain and water.A newly Youjiang secondary active fault,40km long,NW-tren-ding extending,is discovered between Bama-Mashan fault and the Youjiang fault.Combined withseismic geological data,the interpretation results are compared and verified.In the process of imagemerging,the KL transformation,HIS transformation,Multiplicative transformation,Brovey trans-formation and Wavelet transformation are completely compared.With principle components analysisof merged image,Multiplicative transformation is selected to produce enhanced image and interpreta-tion map.The feature of active fault is outstanding ultimately.