The invention provides cell penetrating peptide-nucleic acid conjugates having the formula P-L-N, wherein P is a cell penetrating peptide, N is a nucleic acid, preferably an oligonucleotide and more preferably a siRNA, and L is a hydrophilic polymer, preferably a polyethylene glycol (PEG)-based linker linking P and N together. Compositions, methods of use and methods for producing such conjugates are also disclosed.