Abstract: On the basis of the practice of the Sino-U.S. cooperative geological mapping in the East Kunlun Orogenic Belt and through the comparative analysis of several geological mapping examples completed recently by USGS, we have a further knowledge of the method and idea of America geological mapping. Although the application of geophysics and 3S technology in geological mapping is in continuous development, the fundamental method and idea of America geological mapping and the style of geological reports remain the same ever since the establishment of USGS. The concept of “mapping all lithological unites” hasn′t changed within a difficult course of 130 years along with USGS′s evolution. The mapping method of “geological features guiding geological trails” has been always been followed in America geological mapping historty. Whereas, high accuracy geophysical mapping method commonly applied in thick-bed weathering crusts of Australia and ice-snow covering areas of Canada is not used in the geological mapping of orogenic belts, but the remote-sensing technique provides an important support for the mapping of bedrock areas of orogenic belts. The key of high efficiency of America bedrock areas mapping can not be interpreted by using advanced geophysical and remote-sensing techniques. In fact, utilization of existing geological results, standardized mapping work mode, rational aiming of field mapping and scientific research, the concise geological report, and the GIS application are quite detrimental.