Solid dispersions of silybin and poly(ethylene glycol) (PEG) 6000 were prepared by fusion-cooling. T-wt% and Delta(fus)H(w)-wt% diagrams have been constructed by DSC method. A eutectic point with wt(sily)%=33.3 and T-mE=324.3 K was determined. IR spectroscopy and X-ray diffraction results indicates that the spectrum can be regarded as the superposition of those silybin and PEG 6000. There was no significant change in the crystal structure of silybin and PEG 6000 in their solid dispersion formulations. The experimental T-wt% and Delta(fus)H(w)-wt% diagrams were fit with fair agreement by Flory-Huggins model. (C) 2005 Elsevier B.V. All rights reserved.