In present work, the solubility of silybin in aqueous dextran solution at the temperature range from (293.15 to 313.15) K was measured by a solid liquid equilibrium method. Experimental results reveal that the solubility of silybin is increased with the increase both in dextran's concentration and temperature. With the increase in dextran's concentration, the transport enthalpy and entropy for silybin from water to aqueous dextran solution are decreased within a negative region. The transport enthalpy is more negative than the entropy term. A modified UNIQUAC model was used to correlate solubility data.