The utility model discloses an independent C type LNG tank model test device, including 6-degree of freedom motion platform, control system, camera and jar body, the jar body is the independent C type jar body, the three-layer heat preservation is installed to the periphery of the jar body, the preceding bottom of the jar body is fixed on the base, jar the body back bottom with the base forms along jar axial sliding connection of the body, the base is fixed 6-degree of freedom motion platform is last, the both sides of the jar body are equipped with limit structure, internal temperature sensor and the dynamic pressure sensor of being equipped with of jar, temperature sensor with the radio signal that the dynamic pressure sensor transmission was gathered by control system, control system pass through the bunched conductors with the 6-degree of freedom motion platform electricity is connected, be equipped with filling system, blowdown system and evacuation system on the jar body. Adopt the utility model discloses the evaporation rate model test of independent C type LNG tank can be carried out and model test is rocked.