Fusion gene consisting of dextran-binding domain from Leuconostoc mesenteroides subsp. Mesenteroides (DBD) and human recombinant interferon-beta (IFN-beta) incorporated between the nucleotide sequence encoding for the recognition site of human enteropeptidase (DDDDK) was installed and constructed in Escherichia coli. The overproducing strain of the chimeric protein DBD-IFN-beta consisting of the IFN-beta, spacer including 10 GS-repeats, human enteropeptidase recognition site, and dextran-binding domain from Leuconostoc mesenteroides was constructed. Free human recombinant interferon-beta was obtained as a result of treatment of the chimeric protein DBD-IFN-beta immobilized on sephadex G-25 with human enteropeptidase. The ability of free and immobilized protein to protect human cells from viral infection was demonstrated. The developed approach can be used for purification of the recombinant proteins with different biological activity and possible construction of new immunostimulating and antiviral drugs, growth factors, anti-cancer drugs, etc.