Ovarian cancer is the most common cause of cancer associated mortality in terms of gynecological malignancies,and is difficult to diagnose due to the absence of reliable biomarkers.To identify ovarian cancer specific biomarkers,the present study used a Ph.D.7TM Phage Display Peptide Library to screen for ligands that selectively target HO 8910 ovarian cancer cells.Following 5 rounds of biopan-ning,the phage clone P2 was selected by enzyme linked immunosorbent assay and DNA sequencing,and its character-istics were additionally validated by immunofluorescence and immunohistochemical assays.The results revealed the positive phage were enriched 92 fold following 5 rounds of biopan-ning,and the DNA sequence AAC CCG ATG ATT CGC CGC CAG (amino acid sequence,NPMIRRQ) was repeated most frequently (phage clones,P2,P3,P I 5,P30 and P54).Immuno~fluorescence and immunohistochemical assays revealed that the phage clone P2 was able to bind to ovarian cancer cells and tissues,and not those of cervical cancer.In conclusion,the peptide NPMIRRQ may be a potential agent for the diagnosis of ovarian cancer.