Abstract: Objective To study the growth and metastases of the tumors after orthotopic transplan-tation with hepatocellar carcinoma cell line (Huh-7) in nude rat. Methods Tissue from the tumor inoculated subcutaneously in nude mice with Huh-7 cell line was transferred to the nude rat beneath the skin. Subcutaneous and orthotopic implant models simulating hepatocellar carcinoma was established by suturing histologically intact human tumor tissue on the liver of nude rat. Subsequently,the rate of the orthotopic tumor and their biological properties of tumor growth and metastasis were observed.Tuinorgenecity, invasion，metastasis and morphological characteristics of the implanted tumors were studied by light microscopy, electron microscopy and flow cytometry. Results In orthotopic trans-plant model of nude rat，tumor formation rate was 90.0% and metastasis rate of liver was 50.0%.Conclusions The nude rat is more suitable for orthotopic transplant models for hepatocellar carcinoma，and should be valuable for research on mechanism and new therapies for metastasis.

Key words: Nude rat (rnu/rnu), Subcutaneous transplantation, Orthotopic transplantation;Hepatocellar carcinoma