Phage display technology has been used as a powerful tool in the discovery of ligands specific to receptor(s) oil the surface of a cancer cell and could also impact clinical issues including functional diagnosis and cell-specific drug delivery. After three rounds of in vitro panning and two rounds of reverse absorption, a group of phages capable of addressing BEL-7402 enormously were obtained for further analysis. Through a cell-based ELISA, immunofluorescence, FACS, and in vivo binding study, WP05 (sequence TACHQHVRMVRP) was demonstrated to be the most effective peptide in targeting four kinds of liver cancer cell lines (BEL-7402, BEL-7404, SIVINIC-7721, and HepG2), but not the normal liver cell line HL-7702. In conclusion, the peptide WP05 which was screened by in vitro phage display technology was proved to be a targeting peptide to several common hepatocellular carcinoma cell lines. (c) 2006 Elsevier Inc. All rights reserved.