Abstract: The diamondback moth (DBM), Plutella xylostella (L.) is a key insect pest on cruciferous plants all over the world. Olfactory perception is critical for survival and reproduction in insects, and correspondingly provides a new target to control DBM. Hereby, an odorant binding protein (OBP) gene from P.xylostella,PxylOBP13 (GenBank accession number:KT156679) was cloned; the bio-information characteristics were analyzed; and a phylogenetic tree was constructed. The results showed that the full-length of open reading frame of PxylOBP13 is 387 bp and encodes 128 amino acids; PxylOBP13 contains 6 conserved cysteine residues and the conserved domain of odorant binding protein family, and 3 hydrophobic regions which are potential binding sites for hydrophobic odorants. The protein molecular mass was predicted as 14.33 kDa with an isoelectric point of 7.55, but the N-terminal without signal peptide; the similarity of sequence between PxylOBP13 and six lepidopteran insects can reach above 50%. The results can provide theoretical support for further research on the function of OBPs in DBM and development of effective management of DBM based on olfactory mechanism.