There are still many controversies about the fluid types，mechanism and the architecture of sand bodies formed by gravity flow in deep water. Based on the detailed analysis of Permian deep-water sedimentary outcrops in Karoo Basin of South Africa，Eocene-Oligocene calcareous turbidite outcrops in Tuscan Basin of Italy and a large number of deep-water cores from Upper Jurassic to lower Cretaceous in the North Sea of England，the sedimentary types formed by deep-water gravity flow and their characteristics are redefined，the deep-water turbidite deposition model is constructed，and its oilgas significance is further discussed. The results show that the deep-water gravity flow deposits can be divided into mass transport deposits（MTD）and turbidite deposits；the former is dominated by underwater mud-supported clast flow with poorly differentiation vertically；and the latter is characterized by turbidity current，debris flow and traction flow deposits from bottom to top，with a large number of bedding structures and well differentiation. Controlled by paleogeomorphology，provenance，tectonic setting，etc.，turbidite deposits show different main flow state and scale，which form different lithology and lithofacies，and they can be divided into gully channel，overflow bank and lobe. Fluid properties determine the physical properties，internal heterogeneity and exploration value of reservoirs. The reservoir quality of turbidite deposits and traction flow deposits in turbidity channel，the core of lobes and crevasse splay reservoir are beneficial，while the debris flow deposit and mud-supported clast flow deposit are poor，which are the main factors that cause reservoir heterogeneity.