Abstract: Objective To investigate the function of miR-885-5p mediated by Metadherin(MTDH)in liver cancer metastasis in vivo. Methods MTDH and miR-885-5p expression levels were detected in cancer tissues and paraneoplastic samples of 10 cancer patients.miR-885-5p over-expressed lentiviral plasmid and scrambled negative control plasmid were constructed and infected into human liver cancer cell MHCC-97H and the stable cell lines were selected by flow cytometry.Then MHCC-97H cell of stably expressed miR-885-5p and negative control plasmid were injected into nude mice.After 4 weeks, Luciferase signal was detected by in vivo fluorescence imaging system, and dynamic changes of tumors in nude mice were observed. Results The expression of MTDH in liver cancer tissue sample was 2-5 times higher than that in paraneoplastic sample, while the expression of miR-885-5p in liver cancer sample was 40%- 90% lower than that in paraneoplastic sample.The fluorescence area and intensity decreased 50% after injecting hepatoma carcinoma cell expressed by miR-885-5p in experimental group when compared with control group. Conclusion MTDH shows high-expression in liver cancer samples and it can mediate miR-885-5p.This experiment indicates that miR-885-5p plays an inhibitory role in liver cancer metastasis in vivo.