Objective To investigate the regulatory effect of transforming growth factor-β (TGF-β) on miR-200b-200a-429 expression and the related mechanism. Methods RT-PCR was used to examine the expression of miR-200a, miR-200b and miR-429 in HK-2 cells treated with TGF-β. The miR-200b-200a-429 promoter was amplified by PCR and was cloned into pGL3 basic vector, which was then transfected into HK-2 cells and the luciferase activity of miR-200b-200a-429 gene promoter was detected by luminometer. Results Results of RT-PCR showed that TGF-β down-regulated miR-200a, miR-200b and miR-429 in HK-2 cells 24 h after TGF-β treatment. Vector of pGL3- miR-200b-200a-429-promoter was constructed successfully and was confirmed by sequencing. Dual-Luciferase reporter gene system was used to verify the promoter activity of the constructed reporter gene vector. TGF-β was found to significantly inhibit the activities of miR-200b-200a-429 promoter in HK-2 cells (P<0.05). Conclusion TGF-β may regulate the activity of miR-200b-200a-429 promoter.