Abstract: Objective To investigate whether miRNA-1 may induce rat bone marrow mesenchymal stem cells (rMSCs) differentiation into cardiomyocyte-like cells. Methods rmiRNA-1 expression vector was constructed, rMSCs were isolated, amplified and identified. The fourth passage of rMSCs were transfected miRNA-1 plasmid with Lipofectamine2000 and miRNA-1 expression was then detected by quantitative real-time RT-PCR (qRT-PCR). The mRNA expression of cardiac-specific transcription factor GATA4, NKx2.5 and MEF2C were detected by RT-PCR,cTnI expression was measured by immunofluorescence,respectively,2,4,6 days. Results More than 90% of the cultured rMSCs were positive for CD29 and CD44, which are two significant markers of MSCs and negative for hematopoetic precursor cell markers CD34,leukocyte antigen CD45. After transfection of miRNA-1 in MSCs, the expression level of miRNA-1 was markedly enhanced. The mRNA expression of GATA4, NKx2.5 and MEF2C gradually increased from day 2 to day 6. The cTnI expression was detected by day 4,6. Conclusion miRNA-1 can induce MSCs differentiation into cardiomyocyte-like cells.