Recently, construction of artificial shallow area has been increasing to recover environmental functions of lost natural ones. At offshore end of artificial tidal flats, a submerged dike has been usually installed in order to prevent sediment wash-out by waves. After construction of artificial shallow area, remarkable deformation of bottom topography is sometimes taken place due to wave action, whichresults in losing functions of tidal flats. In this study, characteristics of 3-dimensional water particle velocity field, which effect directly on deformation of bottom topography, in artificial shallow area have been investigated using both hydraulic model tests and numerical calculation. It is revealed that circulating flow is dependent on wave steepness and relative wave height to crest height. Wave height distribution was also discussed.