Objective To explore the mechanisms of Reinforcing Qi and Nourishing Yin in inhibiting tumor metastasis. Methods By duplicating tumor spontaneous and experimental models separately and using immunohistochemical technique and gene chips, some indexes were observed in tumor-bearing mice treated by Reinforcing Qi and Nourishing Yin, including tumor inhibition rate. Inhibition rate of metastasis, changes of hemorheology, effects on tumor angiogenesis and the expression of tumor metastasis-related genes. ...