The western slope of Okinawa trough is an important area for understanding the deep- sea slope deposition. Combined with the existing research results, four seismic sequence boundaries below the sea floor in the west slope of the Okinawa trough have been identified using the detailed interpretation of high resolution seismic data, and accordingly, four main seismic sequences were divided as follows the Holocene sediments (Q4), late Pleistocene sediments (Q3), Middle Pleistocene sediments (Q2) and early Pleistocene sediments (Q1). From the upper slope down, seismic facies transits from the oblique progradational reflection configuration transits to chaotic seismic reflection configuration, and mixed mound seismic reflection units identified in the seismic section are the typical seismic reflection characteristics of landslides and gravity flow deposits, reflecting a high- energy and very unstable sedimentary environment. The axis of the trough is mainly characterized by parallel- subparallel seismic reflection, which shows the stable sedimentary environment of the deep sea and bathyal. The diversity of the seismic reflection structures reflects the complexity of the sedimentary environment and the diversity of sedimentation types on the west slope of the Okinawa trough. The sedimentary stratigraphic structure is affected by many factors. The East China Sea shelf and Okinawa trough have the same vertical Quaternary stratigraphic sequences. But the Quaternary sediments between the western slope of Okinawa trough and the East China Sea shelf have some differences in the sequence boundary, sediments thickness, deformation and occurrence of the sedimentary sequence. Therefore, uncertainties occur in the stratigraphic correlation between two regions using seismic data only.