Abstract: Taking four bucket foundations for object,the factors influencing the dynamic and motion characteristics of the structure are studied by model tests and numerical simulations in still water and regular waves. The results show that:The dynamic characteristics of the structure in still water and motion responses in waves can be predicted reasonably well by MOSES the added mass coefficients of oscillating motion range from 1.4 to 1.6,which are greater than the recommended value of 1.2 in ship dynamics;With the increase of draft,the heave motion of the structure shows an increasing trend while the rocking motion shows a decreasing trend;As the water depth increases,the oscillating motion of the structure decreases,that is to say,the vertical motions are enhanced in shallower water.