Process for the inactivation of viruses

The invention relates to a process for the inactivation and/or elimination of coated and/or noncoated viruses from a plasma protein solution. A process for the inactivation and/or elimination of coated and/or noncoated viruses from a plasma protein solution by addition of an ammonium salt at alkaline pHs is described, in which a chromatographically prepurified plasma protein solution is subjected to an incubation at room temperature and at an ammonium salt concentration of 13 to 22% by weight, pasteurized at approximately 60° C. for several hours after separation of the precipitates and removal of the ammonium salt down to a residual content of less than 0.5 mol/l and then processed to give a therapeutically employable plasma protein preparation.