The aim of this study is to clone the mouse T-bet promoter and enhancer, construct and identify the firefly luciferase reporter gene plasmid pGL4.10-TBX21pr-CNS for T-bet transcription regulation study and its function in signaling of multiple sclerosis. The promoter and CNS of T-bet were predicted by bioinformatics assay. The predicted fragment of mouse T-bet promoter plus CNS was amplified by PCR and cloned into pGL4.10. The recombinant plasmid pGL4.10-TBX21pr-CNS was transferred into Escherichia coli DH5α. The positive clone was identified by double digestion with Kpn I and Sfi I and DNA sequencing. Finally, pGL4.10-TBX21pr-CNS was cotransfected with pRL-TK into 293T cells and Jurkat cells, pRL-TK and pGL4.10 as a control. The luciferase activity in 293T cells (P = 0.012 2) and Jurkat cells (P = 0.002 2) was higher than that of the control group. A fragment of 1 028 bp mouse T-bet promoter plus 1 308 bp CNS was successfully cloned and the firefly luciferase reporter gene plasmid pGL4.10-TBX21pr-CNS was constructed. In 293T cells and Jurkat cells, pGL4.10-TBX21pr-CNS has the promoter functions. This work offers a basic material for the research of T-bet transcription.