LEAFY/FLORICAULA (LFY/FLO) is a family of plant-specific transcription factors, which plays an important role(s) in the regulation of floral organ formation and development. So far, LFY regulation on floral development in wild soybean has not been reported in the literature. In this study, the LFY gene, GsLFY, has been isolated from Glycine soja, and characterized with molecular and transgenic techniques. The cDNA for GsLFY gene is 1224 bp in length and contains an open reading frame encoding a polypeptide of 407 amino acids. Quantitative RT-PCR analysis shows that GsLFY is prominently expressed in various tissues, including roots, flowers and seeds. Among the four floral organs, GsLFY is expressed highly in sepals and stamens while weakly in the petals and carpels. Yeast two-hybrid experiments show that GsLFY possesses transactivation activity while transient expression analysis with Arabidopsis thaliana protoplasts shows that GsLFY protein is localized in the nucleus, supporting the notion that GsLFY is a transcription factor. The GsLFY transgenic tobacco plants flower about 29 days earlier than the wild-type plants, thereby providing a potential rationale for developing new soybean varieties with altered flowering time.