We have extended our study on structure/activity relationship studies of insect peptide alloferon (H‐His‐Gly‐Val‐Ser‐Gly‐His‐Gly‐Gln‐His‐Gly‐Val‐His‐Gly‐OH) by evaluating the antiviral effects of new alloferon analogues. We synthesized 18 alloferon analogues: 12 peptides with sequences shortened from N‐ or C‐terminus and 6 N‐terminally modified analogues H‐X1‐Gly‐Val‐Ser‐Gly‐His‐Gly‐Gln‐His‐Gly‐Val‐His‐Gly‐OH, where X1 = Phe (13), Tyr (14), Trp (15), Phg (16), Phe(p‐Cl) (17), and Phe(p‐OMe) (18). We found that most of the evaluated peptides inhibit the replication of Human Herpesviruses or Coxsackievirus B2 in Vero, HEp‐2 and LLC‐MK2 cells. Our results indicate that the compound [3‐13]‐alloferon (1) exhibits the strongest antiviral activity (IC50 = 38 μm) among the analyzed compound. Moreover, no cytotoxic activity against the investigated cell lines was observed for all studied peptides at concentration 165 μm or higher.