To obtain the cDNA sequence of CobHLH2 transcription factor in Cornus officinalis.Methods:Based on the c101916_g1 sequence from the transcriptome data of C.officinalis as the reference, a pair of specific primers were designed at the 2 ends of its open reading frame using Primer Premier 5.0 software.The total RNA of Cornus officinalis fruits was extracted and reversed transcribed into cDNA as the model.The CobHLH2 sequence was obtained by PCR amplification, purification recovery and clone sequencing.Its basic structure and function through bioinformatics analysis were understood.Results:The ORF of CobHLH2 was 795 bp in length, encoding 264 amino acids and it was a hydrophilic protein.The secondary structure of CobHLH2 protein mainly was Random curl and α-helix, and β-turns and extended chains were less.The analysis of multiple sequence alignments and phylogenetic trees showed that the amino acids sequence of CobHLH2 shared high homology with bHLH transcription factors of Camellia sinensis and Actinidia chinensis.Conclusion:The cDNA sequence of CobHLH2 from C.officinalis was cloned for the first time and bioinformatics analysis was performed, which would lay the foundation for further study on the structure and function of bHLH transcription factors.