Here, we analyzed the transcriptomes of Brassica campestris L. ssp. chinensis Makino under the treatment of a combination of red (R) and blue (B) light. In total, 5,643 differentially expressed genes (DEGs) were found under the R and B combination compared with the white light. An analysis of the DEGs enriched in photosynthesis and antenna proteins showed that there were many more upregulated subunits in PSII than those in PSI. The DEGs encoding the cytochrome b6f complex, photosynthetic electron transport, ATP synthases, and key genes involved in chlorophyll (Chl) and carotenoids (Car) biosynthesis were also upregulated. In addition, real-time PCR indicated that 13 of 15 genes showed the similar expression patterns with the RNA-seq data. The R and B combination might promote photosynthesis by specifically regulating Chl biosynthesis, thus accelerating the growth and development of plants and providing a valuable reference for vegetable production in factories and variety breeding. [ABSTRACT FROM AUTHOR]