Cell wall invertase （CWIN） is an enzyme that catalyzes sucrose hydrolysis to glucose and fructose， and plays an important role in plant growth and development. To explore the function of GmCWINs in plant architecture， particular in plant height and branch number， GmCWIN3， a member of GmCWINs family was cloned in our study. The sequence analysis results showed that the total CDS length of GmCWIN3 gene was 1728 bp and it encoded 575 amino acids.The secondary structure of GmCWIN3 protein exhibited that the irregular coil structure accounted for the largest proportion （48.17%）， and the tertiary structure of the protein revealed that GmCWIN3 encoded a cell wall invertase. Except for several photo-responsive cis-acting elements， some elements associated with the process of growth and development were also found in the promoter region of GmCWIN3， such as auxin responsive element， gibberellin responsive element and circadian rhythm element， etc. Further， through the assay of exogenous spraying different hormones， it was found that GmCWIN3 gene could rapidly respond to the induction of auxin and gibberellin in the initial reaction period. The GmCWIN3 gene overexpression vector was constructed and the transgenic GmCWIN3 Arabidopsis plants were obtained. The cell wall invertase activity and sucrose content of the transgenic Arabidopsis and wild type plants were measured. The results showed that the cell wall invertase activity of transgenic plants was significantly higher than that in the wild type plants， and the sucrose content was significantly decreased. Additionally， the phenotype identification exhibited that the plant height and branch number of the transgenic plants were significantly increased compared with the wild type plants. In summary， this study speculated that GmCWIN3 gene may be involved in the development of regulating soybean plant height and branch number mediated by hormones signaling process through the regulation of sucrose hydrolysis. Our study laid a foundation for further exploring the molecular mechanism of GmCWIN3 in regulating soybean plant architecture related traits.