The dynamics of the deep-sea Bottom Boundary Layer (BBL) directly control the deep-sea sedimentation process, making it the most important energy and material exchange layer in deep-sea science. According to existing sporadic observations, BBL dynamics controlled by multi-scale motions in the ocean differ greatly from current theories, and there remains a lack of systematic quantitative studies on the deep-sea sedimentation process influenced by BBL dynamics. Based on the theoretical framework, sporadic in-situ observations, and numerical and laboratory research, the following points are reviewed and summarized herein: \mathrm{①} Basic characteristics of BBL flow and its turbulent characteristics; \mathrm{②} Effects of tides, internal waves, mesoscale eddies, and large-scale circulation on the BBL dynamics in the deep sea. This review provides a background for further research on deep-sea sediment dynamics based on observations of BBL dynamic processes.