Based on the P-y curve to simulate the interaction behavior between SCR and soil, the influence of the seabed model on the dynamic response of SCR is studied using an elastic foundation beam simulated flow line. The riser-soil interaction depends on several factors, such as soil properties, riser characteristics, and the development of trenching. Current most methods for modeling the seabed in interaction with a SCR approximate the behavior of the seabed soil by linear or nonlinear spring system. However, these methods do not take account for certain factors, such as the plastic deformation of soil and suction effect. The realistic P-y curve is simulated the relation of the seabed resistance force and the vertical penetration of the riser into the seabed during its interaction, the details include: (1) the dynamic responses of SCR with seabed are conducted in hysteretic load-penetration curve, the development of trenching and the envelop curve of the seabed contributed resistance when a case is subjected to cyclic heave motion and linear wave; (2) time histories of the vertical displacement, bending moment, effective tension and stresses are performed to investigate the influence of the nonlinear seabed stiffness model on the dynamic response at TDP of SCR. The results show that the seabed model has the significant influence on the dynamic responses except for the axial effective tension. The foundation element well simulates the part of riser contact with seabed, and the load-penetration curve clearly shows the mobilization and release of suction.