Sensory neuron membrane proteins (SNMPs) play an especially important role in insect pheromone communication. However, the SNMPs for the Asiatic rice borer, Chilo suppressalis (Walker) (Lepidoptera: Pyralidae), a notorious rice pest, remain uncharacterized. Here we report the cloning and characterization of two novel SNMPs from the C. suppressalis, CsupSNMP1 and CsupSNMP2. The CsupSNMP1 and CsupSNMP2 cDNAs contained open reading frames (ORFs) of 1,572 and 1,569 bp, encoding proteins of 523 and 522 amino acid residues, respectively. The amino acid identity between the two deduced CsupSNMPs was low (30% identity), but they shared a high degree of similarity to previously characterized SNMP1s or SNMP2s from other moth species, which is consistent with phylogenetic analysis in which CsupSNMP1 and CsupSNMP2 are clustered into two distinct groups based on their amino acid sequences. The expression patterns of CsupSNMPs in various adult tissues and in different developmental stages were determined by real-time quantitative polymerase chain reaction. The results showed that both CsupSNMP1 and CsupSNMP2 were abundantly expressed in the male and female antennae, reaching their maximum in the adult stage, suggesting the two genes are involved in the process of olfaction. Low levels of CsupSNMP2 also were expressed in nonolfactory tissues such as legs and wings, implying possible gustatory roles of the protein in the moth.