Abstract: Based on the study of the characteristics of the sediments of the Xu-2 Member at Jinhe, Shifang, six sedimentary assemblages are designated and their ten features are described. It is considered that the sandstone of the Xu-2 Member is formed as a result of superim-position of six major fluvial sedimentations. Through the studies of the features of the fluvial sediments, as well as their mineralogical composition and grain size, five types of sedimentary environment of the Xu-2 sandstone within the Sichuan Basin are distinguished and the extent of their distribution is discussed respectively. Thus, the bank line of the ancient river for the sedimentation of the late Triassic Xujiahe stage of the Sichuan Basin is deduced.