Abstract： Objective To explore the expression of miR-30d-5p in cervical cancer and its effect on malignant biological behavior of cervical cancer cells.Methods qRT-PCR was used to detect the expression of miR-30d-5p in cervical cancer tissues,adjacent tissues,normal cervical cells and cervical cancer cells.The mimic negative control(mimic NC)and miR-30d-5p mimic were transfected into SiHa cells,and the transfection efficiency of miR-30d-5p was detected by qRT-PCR.CCK-8 and cell clone formation experiments were used to detect cell proliferation.Flow cytometry was used to detect cell apoptosis.Scratch wound healing assay and Transwell assay were used to detect cell migration and invasion,respectively.Western blot was used to detect the expression of cell apoptosis and invasion-related proteins.Results Compared with adjacent tissues,the expression level of miR-30d-5p in cervical cancer tissues was significantly down-regulated(P<0.01).Compared withEct1/E6E7 cells,the expression level of miR-30d-5p in cervical cancer cell lines was significantly decreased(P<0.01).Overexpression of miR-30d-5p inhibited the proliferation,migration and invasion of SiHa cells and promoted apoptosis(P<0.01).In addition,overexpression of miR-30d-5p significantly down-regulated the expression levels of Bcl-2,N-cadherin and Vimentin(P<0.01),and significantly up-regulated the expression levels of Bax,cleaved caspase-3 and E-cadherin(P<0.01).Conclusion miR-30d-5p is significantly down-regulated in human cervical cancer tissues and related cervical cancer cell lines.miR-30d-5p can inhibit cervical cancer cells in vitro by inhibiting cell proliferation,migration and invasion,suggesting that miR-30d-5p may be a potential new target for diagnosis and treatment of cervical cancer patients.