Great Sanjiang region is an important oil and gas resources succeeding district in eastern China. In this study, a set of conglomerates was found at the bottom of Muling Formation in Linkou basin. Based on an analysis of gravel composition and sorting as well as sedimentary characteristics, combined with the paleocurrent recovery and seismic data interpretation, the authors have concluded that the set of conglomerate is on the whole of alluvial fan facies, the river conglomerate deposition and overflow conglomerate deposition constitute the dominant depositions, and the provenance mainly came from the Zhangguangcai Mountain in the west of the basin. Combined with the seismic data analysis, it is held that the deposition model of the study area was the direct transition from the alluvial fan to the shallow lake subfacies in the period of Muling Formation.