Auxin binding protein (ABP) plays an important role in auxin signal transduction and the regulation of plant growth and development. To study the function and expression features of the ABP gene in sugarcane, we cloned an ABP gene from a sugarcane cultivar (Badila) using RTPCR. Sequence analysis showed that it contained a 615 bp open reading frame (ORF) and encoded a deduced protein of 204 amino acids. It was designated as ScABP4 because of the multiple sequence alignment and phylogenetic tree analysis results revealed that it had closer relationships with ABP4 in Sorghum bicolor and Zea mays. It was cloned into the prokaryotic expression vector pGEX6P1 and expressed a 22.5 kD protein successfully in E. coli. Subcellular localization assay showed that ScABP4 protein is located in the reticular of cytoplasm and on the cytomembrane; protein structure prediction showed that it has a signalpeptide, speculate it may be stored in the endoplasmic reticulum, and exert its function on the plasma membrane. qRTPCR showed that ScABP4 expressed in bud, root, stem and leaf in sugarcane with the highest expression level in bud. ScABP4 was upregulated by IAA or dark treatments indicated that ScABP4 might participate in sugarcane responses to auxin, and involved in light signaling pathway(s). In addition, the expression of ScABP4 in sugarcane was induced by ABA, JA, SA and CuCl₂ but was downregulated by CdCl₂. These results indicated that ScABP4 might involve in the sugarcane resistance to disease, osmotic and heavy metal stress, which provides the basis for further studying the functions of ScABP4.