Disclosed is a CNG tube trailer of the type in which it is constituted of a plurality of CNG tubes 13 to be charged with Compressed Natural Gas and a skid case 12 of which the plurality of CNG tubes 13 are installed therein. A refrigeration system for maintaining an internal air of the skid case 12 at a low temperature so as to enhance a charging efficiency of the CNG tube is installed at a one side of the skid case 12. This CNG tube trailer can make the charging efficiency of the CNG tube to be increased by maintaining an internal air of the skid case 12 at a low temperature. Also, it can accomplish approximately 240% enhancement of the charging efficiency in comparison with operation of the CNG tube trailer according to the prior art, which is filled with CNG under the high pressure without employing any refrigeration system. Since the CNG tube trailer according to the present invention can transfer CNG under a low pressure, it is possible to accomplish a stability of transportation. Because the CNG tube trailer can uniformly maintain the charging quantity of CNG regardless of weather, it allows for the uniform charging of CNG in a manner far more efficient than heretofore known and thereby resulting in a considerable reduction in costs.
