Antisense-oligonucleotide can be employed as gene expression inhibibor and potential therapeutic agents. However,many classes of oligonucleotide are polyanion and cannot penetrate cell membrane. It is known that several peptides,including fusion peptide and signal peptide, have the properties of transmembrane and/or cell nucleus localization.The synthesis and biological activity of antisense oligonucleotide-peptide conjugates are discussed.