In this research, we used $GdCl_3$ (gadolinium chloride) to restrain the function of Kupffer cells and assessed effects on hepatocarcinogenesis and metastasis in the Kunming mouse. A 0.25% $GdCl_3$ solution (10 mg/kg b.w.) was infused via the vena caudalis of each mouse 1 week before inoculation of H22 cells and was continued once per three days. Then we observed the follow indexes 3 weeks after injection of H22 cells: tumor weight, histologic characteristics of tumor tissue by light microscopy, ultramicrostructure of Kupffer cells under the electron microscope, distribution and number of Kupffer cells by histochemical staining, and TNF-${alpha}$ and IFN-${gamma}$ levels in blood-serum and liver tissue by ELISA and RT-PCR. MMP-2 protein expression was tested by immunohistochemistry. The $GdCl_3$ pretreatment had no effect on the quantity of Kupffer cells, but clearly restrained their functions, with decrease of TNF-${alpha}$ and IFN-${gamma}$ levels and elevation of MMP2. Tumor immunity functions were markedly suppressed and tumor growth was accelerated with appearance of metastasis. Furthermore, survival time of trial mice was shortened.