In insects, glutathione S-transferases (GSTs) are multifunctional enzymes playing an important role in metabolizing a wide range of endogenous and exogenous compounds, including plant secondary compounds, insecticides, and odorant molecules. In this study, we identified 14 GSTs from codling moth Cydia pomonella (L.), which is a worldwide internal pest of tree fruit. The cytosolic GSTs contain the conserved glutathione (GSH)binding domain and substrate-binding domain. The microsomal GSTs are transmembrane proteins containing a conserved motif consisting of 16 amino acids. Real-time polymerase chain reaction (RT-PCR) revealed that 10 CpomGSTs were expressed in the antennae. Among them, a novel signal peptide containing GST (CpomGSTd2) was restrictedly expressed in the antennae and the expression levels were significantly higher in male than in female. Phylogenetic analysis shows that CpomGSTd2 shares close relationships with olfactory GSTs of other insects. We prepared the recombinant CpomGSTd2 and determined its GST catalytic property using 1-chloro-2, 4-dinitrobenzene (CDNB) and reduced GSH as substrates. This protein exhibited high GST catalytic activity within the temperature ranged from 25 to 50 ° C and the optimal pH was 7.0. Our results suggest that antenna is important site for GST-mediated biotransformation and CpomGSTd2 may play a role in the odorant degradation for chemosensory perception.