Physical model tests were counducted to predict local scour and maximum scour depth around the large diameter cylinders located in the (sand) seabed under the action of both wave and current . According to the result of tests, an analysis was made on all the factors influencing the scour. The results shows that for the seabed with relative fine grains in shallow water (0.07＜h/L≤0.28),when the relative diameter D/L of the cylinder is within 0.3-0.7,the main effective scour factors around the cylinder in the seabed are diameter D of the cylinder, the wave height H, the wave length L, the velocity Vc of the current and the parameters related to the seabed soil texture. The main parameters influecing the maximum scour depth were analyzed, and the test data were syntherized, to obtain the formula predicting the scour depth around the large diameter cylinder under the of both wave and current.