In order to understand the biological function of soybean SUS family genes, and provides basic information for breeding of high yield varieties and functional utilization of GmSUS genes in soybean, in this study, we performed the genomewide identification and expression analysis of sucrose synthase (SUS) gene family based on published soybean genome sequence. Our results showed that: (1) a total of 12 putative SUS genes (GmSUS1-GmSUS12) were identified in soybean genome. (2) The sequence identity of GmSUS proteins was very high, and all of them had the sucrose synthase domain and glycosyl transferase domain. In addition to GmSUS5, other GmSUS proteins had a conserved serine phosphorylation site at their N terminal. (3) A phylogenetic analysis showed that GmSUS proteins in soybean could be classified into three groups (SUSI-SUSⅢ), and GmSUS genes in the same group exhibited similar intron/exon pattern. (4) 12 GmSUS genes were unevenly located on 10 chromosomes of soybean, and tandem duplication was the contributor to the expansion of GmSUS genes in soybean genome. (5) Expression pattern analysis indicated that GmSUS genes exhibited differential tissue expression patterns. GmSUS8 was highly expressed in seed; GmSUS1, GmSUS7 and GmSUS5 were highly expressed in nodule; GmSUS3, GmSUS11 and GmSUS12 were highly expressed in all examined tissues.