Abstract
This study carried out field observation and numerical simulation for the purpose of clarifying the actual situation of the vertical mixing over artificial mound reef. From an observation result, a layer of a density reversal and the density equality was confirmed in a range of below the mixed layer from sea bottom in the direct above and the down stream of the structure. A value grew big about the energy dissipation rate that it estimated based on an observation result in the same layer, and it was confirmed that vertical mixing occurred. In addition, from a numerical simulation result based on an observation result, the vertical mixing that was similar to an observation result was grasped.