The construction of the subsea tunnel that connects with neighboring countries is very important to the Korean peninsula, surrounded on three sides by the sea. The subsea tunnel may establish a transport network hub, as well as improve the accessibility of the state. Therefore, it is necessary to secure the domestic core technology for the design and construction elements needed for the construction of an subsea tunnel under the high water pressure. Commonly, grouting method is applied in tunnelling construction to prevent damage to soil and inflow of ground water. But it is difficult to apply conventional grouting method to subsea tunnelling construction in the high-pressure condition. In such a condition, the artificial freezing method can enable the tunnel excavation construction to form a watertight zone around the freezing pipes. For a proper design of the artificial freezing method, the influence of salinity on the freezing process has to be also considered. However, there are few domestic tunnel construction that applied the artificial freezing method and it is not clearly identified how the pressure and the salinity impact on the freezing of the soil. In this paper, the experiments were performed to identify the epidemiological characteristics of the frozen soil. Strength of frozen soil was evaluated through the uniaxial compression test and the change of thermal properties caused by freezing process was analyzed through the thermal conductivity measurement. Also, the geothermal chamber was designed and manufactured to perform the large-scale freezing test. The temperature in silica sand mixed with saline water was measured during the freezing process to evaluate the effect of salinity on the frozen rate, which is significant in designing the artificial freezing method in subsea tunnelling. In addition, a numerical analysis is conducted by using a finite element analysis program to verify the results of the chamber test and perform the parametric study.