The present invention relates to an apparatus for measuring a thermal conductivity coefficient of fine grained soils and, more specifically, to an apparatus for measuring a thermal conductivity coefficient of fine grained soils according to variations in loads and dry density which can continuously measure relatively accurate dry density, additionally reflect changes in load conditions, minimize sample disturbance when a thermal conductivity coefficient is measured, and minimize measuring errors of a thermal conductivity coefficient and dry density. The apparatus for measuring a thermal conductivity coefficient of fine grained soils according to the present invention comprises: a sample holding part for holding an experimental sample; a pressurizing part which is located on the sample holding part and pressurizes the sample flat; a bottom member which is the bottom of the sample holding part and has multiple pores; a thermal conductivity measuring part for measuring a thermal conductivity of the sample in the sample holding unit; a subsidence measuring part for measuring a subsidence level of the sample by the pressurizing part; a holding part for holding the sample holding unit; a supporting part for supporting the sample holding part in order to separate the sample holding part from the bottom of the holding unit; a draining part which is extended from the bottom member through the supporting part to one side of the holding part; and a filling member for filling a space between the sample holding part and the holding part. [Reference numerals] (AA,CC) Dead weight;(BB) Specimen