A process for preparing a hemostatically active preparation containing von Willebrand factor (vWF) from a fraction of human plasma by chromatographic purification of a vWF-containing plasma fraction on an anion-exchange material which has the anion-exchanging groups on grafted polymeric structures (tentacle materials), collecting a vWF-containing fraction, followed by purification of said fraction using gel permeation to prepare a purified thermally stable vWF-containing preparation; and heating the preparation for inactivating viruses.