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<i>bHLH</i> transcription factors play an animated role in the plant kingdom during growth and development, and responses to various abiotic stress. In this current study, we conducted, the genome-wide survey of <i>bHLH</i> transcription factors in <i>Liriodendron chinense</i> (Hemsl) Sarg., 91 <i>LcbHLH</i> family members were identified. Identified <i>LcbHLH</i> gene family members were grouped into 19 different subfamilies based on the conserved motifs and phylogenetic analysis. Our results showed that <i>LcbHLH</i> genes clustered in the same subfamily exhibited a similar conservative exon-intron pattern. Hydrophilicity value analysis showed that all <i>Lc</i>bHLH proteins were hydrophilic. The Molecular weight (Mw) of <i>Lc</i>bHLH proteins ranged from 10.19 kD (<i>LcbHLH</i>15) to 88.40 kD (<i>LcbHLH</i>50). A greater proportion, ~63%, of <i>Lc</i>bHLH proteins had a theoretical isoelectric point (pI) less than seven. Additional analysis on the collinear relationships within species and among dissimilar species illustrated that tandem and fragment duplication are the foremost factors of amplification of this family in the evolution process, and they are all purified and selected. RNA-seq and real-time quantitative PCR analysis of <i>LcbHLH</i> members showed that the expression of <i>LcbHLH</i>35, 55, and 86 are up-regulated, and the expression of <i>LcbHLH</i>9, 20, 39, 54, 56, and 69 is down-regulated during cold stress treatments while the expression of <i>LcbHLH</i>24 was up-regulated in the short term and then later down-regulated. From our results, we concluded that <i>LcbHLH</i> genes might participate in cold-responsive processes of <i>L. chinense</i>. These findings provide the basic information of <i>bHLH</i> gene in <i>L. chinense</i> and their regulatory roles in plant development and cold stress response.