Objective To understand the basic features of EXP gene family and build a platform for further research on its function.

Method The Bioinformatics methods were used to analyze 35 EXP gene family members of the genome-wide sequence in Eucalyptus grandis (EgrEXP1~EgrEXP35).

Result The result indicated that E. grandis EXP genes located in 8 different chromosomes, and the subcellular localization were located on the cytoplasmic membrane. Most of the family members had a signal peptide. The proteins encoded by the E. grandis EXP genes were composed by alpha helix, extending chain, random coil and beta corner. Phylogenetic analysis revealed that E. grandis EXP protein shared close relationship with those in Populus trichocarpa. The 35 E. grandis EXP expression patterns were significantly different in the tissues including immature xylem, mature leaf, phloem, shoot tips, xylem and young leaf.

Conclusion The EXP expression pattern of E. grandis was different among family members. It could be inferred that EgrEXP17 and EgrEXP18 may play an important role in the process of wood formation in E. grandis.