The new conceptual artificial seabed can effectively improve the adaptability of disastrous marine environmental factors such as strong winds, huge waves and surface currents, but the considerable impact force generated by internal solitary waves is a key factor affecting the operation safety of the artificial seabed. This paper presents a study on hydrodynamic forces and flow field characteristics of the new conceptual artificial seabed under the action of internal solitary waves. First of all, the eKdV equation was used as the theoretical model. A three-dimensional numerical flume was established by using the wave-making method of velocity inlet, and the numerical wave-making of internal solitary waves was achieved. On this basis, the numerical waveform was compared with the theoretical and experimental waveforms, and the feasibility of the numerical method was verified. Finally, hydrodynamic forces exerted by internal solitary waves on the artificial seabed were calculated, the characteristics of forces induced by internal solitary waves of various amplitudes on the artificial seabed were studied in detail. Besides, the velocity field and the vorticity field around the artificial seabed were analyzed. The results show that, with the increase of the amplitude of the internal solitary wave, the drag force, vertical force and lift force on the artificial seabed gradually increase, and the drag force and vertical force are much greater than the lift force. When the internal solitary wave passes through the artificial seabed, both the particle velocity of the fluid and the vortex intensity around the artificial seabed increase. This study provides an effective numerical calculation method for the prediction of internal solitary wave forces and the analysis of flow field characteristics of large underwater engineering structures.