Abstract: 【Objective】 In Ningbo City, China, since the rail way mainly goes through marine deep soft soils, the artificial freezing method was widely used during the construction. The thermal physical properties of typical soil layers in this area are the thermotical foundation for the design of freezing method. The study of the thermal physical properties of typical marine soil in this area could provide the design of freezing method with some references, promoting the application of the freezing method in the area.【Method】Taking the typical soil layer of mucky clay, silty clay and sandy silt in Ningbo City as the research samples, the tests of freezing temperature, thermal physical parameters and frost heave and thawing settlement in closed and open systems were conducted. The effects of soil, freezing and thawing conditions on the freezing temperature, thermal physical properties and freezing/thawing properties of marine artificial frozen soil were studied. 【Result】The results showed that the freezing temperatures of the three types of soils were ranged from -0.43 to -0.23 ℃(descending in the order of sandy silt, silty clay, mucky clay). The thermal physical properties of different kinds of soils were different, but the values of thermal conductivities of soils at natural temperature were substantial consistent with that of the volumetric heat capacities. It was showed that the sandy silt was the largest, the silty clay was the second, and the mucky clay was the smallest. The thermal physical properties of different kinds of soils were different. The thermal conductivity, volumetric heat capacity and thermal diffusivity of frozen soil were all higher than that of soil at natural temperatures. The thermal conductivity of frozen soil was about 1.37-1.77 times of that of soil at natural temperature. The larger the soil particles, the greater the difference of thermal conductivity between the frozen soil and soil at natural temperature. The frost heaving ratio and thawing settlement coefficients of three kinds of soil were quite different. The higher the frost heaving ratio of soil, the larger the thawing settlement coefficient(descending in the order of mucky clay, silty clay, sandy silt). The frost heaving ratio and thawing settlement coefficient of the soil in the open system were 1.23-1.88 and 1.21-1.84 times of the value of the soil in the closed system.No matter the freezing and thawing conditions were open system or closed system, the process of thawing settlement of each soil layer was similar. Thawing process could be divided into three stages of slow thawing settlement, rapid thawing settlement and stable thawing settlement. 【Conclusion】The freezing temperature, the thermal physical properties and freezing-thawing properties of marine soils were closely related to the soil, the state and the freezing-thawing conditions. In the design and construction of artificial freezing method of marine soil, the difference of thermal physical properties should be fully considered.