Abstract: Currently, a lot of tests have been done to study the change of thermal properties of silt soils with a factor. However, in the studies on the effect of a factor, other influencing parameters have not been kept unchanged. In order to build the precise relationship between thermal properties and the influencing factors of silt soils, more strict experiments are required. In addition, few tests on silt's thermal properties have been reported yet. In the present studies, a series of laboratory tests have been carried out to examine the relation between thermal conductivity and moisture content of the silt soils. In these tests, the effects of moisture content were examined individually, while the other factors (such as dry density and void ratio) are kept constant. It is indicated that the thermal conductivity increases with the increase in moisture content, and follows the logarithmic law which is consistent with sand. Subsequently, comparisons between present studies and other results reported in the previous studies were conducted. Finally, the heat transfer mechanism of the silt soil is studied to explain the present results.