The present paper reports the model tests of the sea ground leveling equipment used for leveling the dredging trances by drag-suction dredger at Nagoya harbor.
　The laboratory tests were carried out using model blades the length of which are 100mm～600mm, with various curvature and various angle of sweep-back in consolidated sand with some moisture, satuirated sand and consolidated clay.
　The results are summerized as follow
　1) With the increase of angle of sweep-back, leveling resistance becomes smaller and slmaller and leveling effect becomes better, but the direction of the course of blade shows the marked tendercy to be curved.
　2) Leveling resistance was expressed as follow:
　H=H0+K1(Ws+V),　　H=K2V
where, H, H0, Ws and V are respectively horizontal component of resistance, initial horizontal component of resistance, weight of soil, and vertical component of resistance, K1 and K2 are constant determind from sand, model blades and depth of excavation.
　3) Suppose that height of model blade is infinity ,volume of sand which is pilid up before blade is expressed theoretically as follow.
　Q=KtB2(1-e(-s/KB))
where, Q, t, B, S and K are sand volume, depth of excavation, length of model blade, leveling stroke and constant determined from sand and curvature of blade respectively.
　4) When the pilid up sand volume before blade is saturated, leveling resistance does not concern with a curvature of the blade.