Abstract: Two typical types of deepwater sedimentary sequence occur in the northeast Indian Ocean，which have been found on the Bengal fan and Ninetyeast Ridge，respectively. The turbidity and hemipelagic sedimentations are dominant in the Bengal fan，where the major composition of sediments are terrigenously derived from the denudation of Himalayan Mountains，while the pelagic sedimentation in the Ninetyeast ridge，where the major one from calcareous planktonic tests produced in ocean environment. Although there is an essential difference between them in material constituent and forming mechanism，both of two sedimentary sequences were deeply affected in their respective accumulation process by Himalayan tectonics. Using the data and samples of the holes DSDP218，ODP717，ODP758 and some others from the northern Indian Ocean，in the paper we make a comprehensive study of them in sedimentology，micropaleontology and paleoceanography and establish a correlation of geological events since 9 million years recorded in proximal fan，distal fan and ridge，respectively. Our results show that the most important and influential events took place at～35 Ma and～08 Ma among all those episodes associated with the Himalayan uplifts.