Sedimentary types，characteristics and depositional model of gravity flow developing in the upper submember of the first member of Liushagang Formation in Weixi’nan Sag were studied based on drilling，logging，core，experimental data and 3D seismic. The results show that there are three types of gravity flows including debris flow，turbidite current and slump deposit in the upper submember of the first member of Liushagang Formation in Weixi’nan Sag，among which debris flow and slump mainly develop in the study region. Debris flow can be divided into sandy debris flow and muddy debris flow according to its lithological composition. The sandy debris flow is characterized by massive structures，argillaceous rigup and floating mud-gravel.Well-developed plastic deformation structures in slumps deposit which shows the characteristics of gravity flow deposits，and retains the characteristics of traction flow deposits. The coupling of lake level change，provenance system，slope broken and source channel controls the sedimentary types and distribution of gravity flow，and two classical depositional models of gravity flow are summarized including north-west provenance delta-faulted slope-erosion channel and west provenance delta-synsedimentary slope broken.