Abstract: To study the effect of TGF - β1 gene silencing with shRNA on the proliferation of human salivary gland mucoepidermoid carcinoma Ms cells. Methods: Ms cells were transfected with TGF - β1 shRNA vector or the empty vector, and the stably transfected cells were selected after exposure to 600 mg/L of G418 for 21 days. The positive clones were identified by RTPCR and immunohistochemical staining. MTT assay, soft agar clone formation assay, flow cytometry (FCM) and transmission electron microscopy (TEM) were used to observe cell proliferation and morphology. Results: TGF- β1 shRNA blocked the expression of TGF- β1 mRNA and protein in Ms cells. The population doubling time (h) of untransfected cells, empty vector transfected cells and shRNA vector transfected cells was 39.2, 40.1, and 45.3, while the percentage of cells in phase G1 was 54.2%,56.8% and 61.7%, respectively. The proliferation index (PI) 0.46, 0.43 and 0.38, and the clonogenecity (%) 34.7, 33.3 and 15.8, respectively, for untransfected cells, empty vector transfected cells and shRNA vector transfected cells. TEM observation revealed that microvilli on the surface of shRNA vector transfected cells were less abundant, the endoplasm web was obviously expanded and the ratio of nucleus to cytoplasm was reduced. Conclusions: Transfection of TGF- β1 shRNA may silence the gene and inhibit cell proliferation.