Detection of metastatic cells is clinically demanded to diagnose metastasis in the early stage and access the therapeutic response to anti-cancer drugs. We applied phage display technology to cultured cells with different metastasis potential and obtained four metastasis associated peptides. The association between peptides and metastatic cells were validated by ELISA as well as biosensor studies. The selected phage-peptides not only bind SW620, the metastatic cell against which the peptides were screened, but also able to capture breast cancer cells of high metastasis. The phage-peptide modified LAPS was able to distinguish metastatic cells from nonmetastatic cells and detect as few as 100 metastatic cells per mL of blood. Thus, LAPS modified with specific phage-peptides may be developed to a new diagnosis approach that can aid the treatment of cancer.