The accurate identification and detailed dissection of the accretionary complex in orogenic belts is not only of direct significance for determining the existence of paleooceanic basin and paleosubduction zone, but also for guiding exploration of regional mineral resources. Thematic geological mapping is an effective means to identify and dissect accretionary complex. However, the high altitude and inconvenient transportation in some dangerous areas make mapping work difficult. The remote sensing geological interpretation can provide useful information for thematic geological mapping. Therefore, this paper tries to carry out the remote sensing geological mapping of the Tuomoerrite area in the northern margin of Qaidam basin, to reveal the exposed rock combination types, spatial distribution and structure features, distribution characteristics, and to extract the regional mineralization alteration information, which can provide a new approach to the identification and dissection of the accretionary complex in orogenic belt. Combination with regional geological data, project geological mapping and remote sensing geological interpretation results, comprehensive analysis demonstrates that the southern section of Tanjianshan Group in the northern margin of Qaidam basin is accretionary complex, which has the structural characteristics of blockinmatrix, develops imbricate thrust faults, double thrust faults and homoclinal closed folds, and associated hydrothermal orogenic gold deposits. The results show that remote sensing geological interpretation can effectively identify and dissect accretionary complex, and can be used as a practical method for thematic geological mapping of accretionary complex.