[en] The radon emanation coefficient (ε) from aquifer rock and the Henry's law constant (H) of radon were determined by measuring activity concentrations using liquid scintillation counter (LSC). For the evaluation of the method, the coefficients were measured at 0, 10 and 20 deg C and the temperature dependency of the coefficients was compared with others. The radon emanation coefficients from the rock particles used in this work are 0.0845, 0.1007 and 0.1308 at 0, 10 and 20 deg C, respectively. The dimensionless Henry's law constants for the groundwater used in this work are 0.994, 1.153 and 2.641 at 0, 10 and 20 deg C, respectively. The results show a good agreement with those in literatures. (author)