Abstract: Basic leucine zipper（bZIP） proteins are transcription factors unique to eukaryotes being widely involved in the regulation of plant growth, development and physiological metabolism. To investigate the function of bZIP transcription factors, this study cloned GmbZIP33（Glyma.03G219300.1） gene encoding the bZIP transcription factor from soybean using PCR. Bioinformatics method was used to analyze the gene and its encoded protein, and qRT-PCR was used to detect the spatiotemporal expression patterns of the gene and its responsiveness to stress. Arabidopsis thaliana with heterotopic overexpression of GmbZIP33 was constructed to analyze the effects of GmbZIP33 on plant phenotype and the expression of flowering-related genes. The results showed that: GmbZIP33 is located on the chromosome 3, with an encoding region of 453 bp, and GmbZIP33 has 91.4% homology with GmbZIP41 of the S-bZIP transcription factor family, indicating that it belongs to the S-bZIPs subfamily. It was found that GmbZIP33, which exhibited the highest expression level in leaves, is responsive to high salt and drought stress. Additionally, GmbZIP33 was demonstrated an obvious circadian rhythm under short day conditions, suggesting its potential involvement in the photoperiod regulation of the flowering complex network. A. thaliana with heterotopic overexpression of GmbZIP33 was constructed, and the transgenic plants exhibited an early flowering phenotype with increased expression of flowering related genes（such as FT, etc.）, indicating that GmbZIP33 is involved in the flowering regulation pathway of A. thaliana and effectively promotes plant flowering. This study provides a foundation for further understanding of the multifunctional regulatory role of GmbZIP33 transcription factor in plant growth and development.