Abstract: Submerged cylinders are widely used in marine construction. Local scour has a great impact on the safety and stability of such buildings. In order to understand the scour characteristics of this type of building under wave and current, a series of scour experiments were carried out in the wave-current flume. The model was installed in a flat sand box in the middle of the wave-current flume, of which the surroundings were covered with non-cohesive sand of median diameter 0.22 mm. The water level is always set as submergence situation. The condition of incident wave and current was changed to observe the local scour development process around the submerged cylinder with various heights. The local scour depth was measured and recorded. A variety of dimensionless parameters were applied to analyze the data and assess their influence on the scour. The result shows that when KC number is fixed, the relative scour depth s/D increases with the relative flow velocity U_cw and Fr. When Fr increases to a certain extent (Fr>0.80), s/D tends to be stable; when U_cw is in a fixed range, depth s/D increases with KC number, and the growth rate gradually becomes slower. The submergence factor K_s gives the relationship between the scour depth of the submerged cylinder and that of the non- submerged one.