The invention provides a tide simulation testing device which comprises flow making cylinders, a demonstration tank and two connecting cylinders, wherein the demonstration tank is arranged parallel to the flow making cylinders and is positioned above the flow making cylinders; the openings of the flow making cylinders are correspondingly connected with the opening of the demonstration tank through the connecting cylinders so as to form a loop flow path; submersible motors are arranged in the flow making cylinders; rotary blades are arranged on rotating shafts of the submersible motors; a plurality of flow guide grid plates are respectively arranged at two end parts of the connecting cylinders. Through the loop flow path formed by the flow making cylinders, the demonstration tank and the connecting cylinders, the submersible motors directly drive the rotary blades to rotate so as to form strong water flow in the flow making cylinders, thus the efficiency in making the flow is effectively improved; the flow is guided through the flow guide plates in the connecting cylinders, the stability of the water flow is improved, uniform tide is formed in the demonstration tank, the tide in ocean can be actually simulated, the simulation effect of the tide is optimized, and the manufacturing cost of the tide simulation testing device is lowered.