Abstract: A Basic transcription factor 3(OsMsr3) gene from Salvia miltiorrhiza Bunge(OsMsr3) was cloned by PCR and RT-PCR,named OsMsr3.The deduced amino acid sequence of SmOsMsr3 were analyzed by the tools of bioinformatics in the following aspects:the chemical composition,hydrophobicity or hydrophilicity,post-translational modification,structural domain and the advanced structure of deduced amino acid sequence.The expressions of SmOsMsr3 in different organs and under stress treatments were detected by real-time fluorescent quantitative PCR.The results showed that the genomic DNA of SmOsMsr3 was 1510 bp long,which contained 5 exons and 4 introns,while its cDNA was 794 bp.The deduced protein were hydrophilic.The second structure prediction indicated α-helix and random coil were the major motifs and NAC domain was included.The sequence composition,structure,and activity sites were highly similar with other BTF3 proteins in plants.The expression of OsMsr3 was the highest in root,followed by that in stem,and the least in leaf.Obvious changes of the expression of OsMsr3 were not Abserved during 24 h treated by ABA,while under the drought stress,the expression was inhibited at first and then increased to control level.