FIELD: medicine, chemistry. SUBSTANCE: invention relates to preparing DNA-base antiviral preparations from animal raw. Method involves addition of chemical agents to DNA-containing biogenic reaction mass to cleave glycosidic bonds in nucleotides under mild conditions and obtain compositionally homogeneous native polymers of the following properties: molecular mass is 300-500 kDa, ratio A/P = 1.0-1.5, RNA content is 3.0-5.0%, protein content is 0.7-1.5%, and metal content is 0.001%, not above. Prepared preparations show activity with respect to HIV viruses, herpes viruses, adenoviruses and influenza viruses being without cytotoxicity. EFFECT: improved method of preparing. 7 cl, 4 tbl
