The Lijiang-Xiaojinhe fault is an important tectonic boundary within the Chuan-dian diamond block. The previous studies suggested that the fault is left-lateral strike-slip supported by the faulted landform characteristics,and considered that the Lijiang Basin has been faulted. In this paper,shallow seismic exploration and borehole exploration are carried out in the basin-concealed section of the Lijiang-Xiaojinhe fault,and the stratigraphic composite section of the fault is established through the analysis of stratigraphic lithology. We found that the Lijiang-Xiaojinhe fault has crossed the Lijiang Basin. The overall form of the concealed section is an asymmetrical positive-flower structure,which is characterized by fault-propagation fold and thrust faults. However,the top of the main fault is characterized by local extension and the main fault had faulted late Quaternary strata.