Abstract: The 4th Member of Xujiahe Formation, Upper Triassic, in the northeastern Sichuan Basin is a key layer for oil-gas exploration. The deposition in the area is affected by multiple provenances. By analyzing the heavy minerals, clastic constituents, debris compositions and paleocurrent directions, it is finally determined that the provenances originate from three directions, namely, Longmenshan, Dabashan and Micangshan. The provenance of the western Yuanba is from Longmenshan fold belt; that of the eastern Yuanba, from the southeast of Dabashan fold belt; that of the central Yuanba, from the mixed accumulation of Longmenshan and Dabashan; that of the western Tongnanba area, from the Micangshan fold belt; while that of the eastern Tongnanba area, from the mixed accumulation of Dabashan and Micangshan.