The human immunodeficiency virus (HIV) is a lentivirus that results in acquired immunodeficiency syndrome (AIDS). HIV treatment involving chemical therapeutic agents has improved the quality of life of HIV/AIDS patients. The present study demonstrates that a hydroxyproline-containing marine collagen peptide (APHCP) derived from Alaska pollack inhibits HIV‑1 infection in the MT-4 human T cell‑line. APHCP inhibited HIV-1IIIB-induced cell lysis, syncytia formation, reverse transcriptase activity and viral p24 production at non‑cytotoxic concentrations; however, APHCP did not inhibit HIV‑2ROD infection in MT‑4 cells. This suggests that the anti‑HIV activity of APHCP is specific to HIV‑1. In addition, substitution of hydroxyproline residues in APHCP with prolines impaired its anti‑HIV‑1 activity, suggesting that the hydroxyl group of hydroxyprolines is required for the anti‑HIV‑1 activity of APHCP. These results suggested that the marine peptide APHCP may be a novel drug candidate in the development of next‑generation therapeutic agents for the treatment of HIV/AIDS.