Aim To investigate the effect of microRNA-30b(miR-30b)on the migration of rat vascular smooth muscle cells (VSMC). Methods Rat VSMC were isolated and cultured in vitro. VSMC were randomly divided into normal control group (no transfection), miR-NC group (transfected miR-NC concentration 50 nmol/L), miR-30b mimics group (transfected miR-30b mimics, concentration 50 nmol/L). Real-time quantitative PCR was used to detect the expression of miR-30b and E-cadherin. The mobility of VSMC was detected by scratch healing test. The migration ability of VSMC was detected by Transwell assay. The expression of E-cadherin protein was detected by Western blot. Results Compared with the normal control group and the miR-NC group, the expression level of miR-30b was increased in the miR-30b mimics group (P<0.05). The results of the scratch-healing experiment showed that the migration ability of the miR-30b mimics group was significantly weaker than that of the normal control group and the miR-NC group (P<0.05). Transwell experiments showed that the migration ability of miR-30b mimics group was weakened (P<0.05). The expression of E-cadherin mRNA and protein in miR-30b mimics group was significantly higher than that in normal control group and miR-NC group (P<0.05). Conclusion miR-30b can up-regulate the expression of E-cadherin, thereby inhibiting the migration of rat VSMC.