The model test is carried out for a new type of movable submerged tensioned moored buoy-type oil and gas external terminal system. The dynamic response of the submerged buoy and the force characteristics of the tensioned mooring are investigated in detail. It is found that the submerged buoy in heading wave condition generates large motions in both wave direction and transverse direction. The tensioned mooring is subjected to impulse loading characteristics. A theoretical basis is provided by the study for the design of the tensioned buoy external terminal system.