Abstract: To study the inhibitory effect of TGF-β1 on human salivary gland mucoepidermoid carcinoma in nude mice lung metastasis by RNA interference and determine the effect of Ki-67, VEGF, and uPAR expression. Methods: A balb/c nu/nu nude mice lung metastatic model was used to test the metastatic ability of Ms  cells. Lung metastatic tumors were experimentally induced by mouse tail vein inoculation of Ms cells, Ms cells transfected with empty vectors, and Ms cells transfected with TGF-β1 shRNA. After the mice were sacrificed, metastatic nodes were counted using a magnifier. The expressions of Ki-67, VEGF, and uPA in the in the nude mice metastatic model were detected by an immunohistochemical method. Results: In vivo, a significant decrease in lung metastasis was observed when mice received tail vein injections of TGF-β1-silenced mucoepidermoid carcinoma cells compared with controls ( P < 0.05 ). The inhibited rate of lung metastastasis in nude mice was 47.6%. The expressions of Ki-67, VEGF, and uPA were down-regulated. Conclusion: Suppression of the expression of TGF-β1 in human salivary gland mucoepidermoid carcinoma Ms cells by RNA interference could inhibit lung metastasis and down-regulate the expression of Ki-67, VEGF, and uPA.