||Chemosensation is an important process used by animals to perceive changes in the environment and to coordinate appropriate responses. The chemosensory system detects a diverse range of chemical cues, including sex pheromone, via different chemosensory receptors. It has been shown that Caenorhabditis remanei females produce a sex pheromone with long-range attractiveness for both C. remanei and C. elegans males. Previous data also implicate the involvement of G protein-coupled receptors (GPCRs) acting in AWA neurons in this perception process. In order to identify the receptors acting within AWA, an in vivo cell-specific pull-down experiment was conducted, followed by a microarray analysis. Less than 300 GPCR-transcripts were identified from the AWA-transcriptional profile. Through transcriptional reporter expression study, nine GPCRs were confirmed to be expressed in AWA from the top-ranked 50 candidates. Through functional tests to the mutants with defective GPCRs, str-164 was shown to be involved in the sex pheromone perception, while 26 GPCR candidates were eliminated. A male-specific GPCR, srd-1, was shown as a promising candidate. It was confirmed to be expressed at the cilia of AWA specifically in males, and was proved to be required for the sex pheromone perception. However, whether this function was mediated uniquely by AWA was still uncertain. The ectopic expression of SRD-1 in the repellent chemosensory neuron caused some weak repellence to the sex pheromone. Six AWA-expressed GPCRs were tested through AWA-specific knockdown, with negative results obtained. The negative results could not demonstrate the requirement of the tested GPCRs in the sex pheromone perception, while could not rule them out, either. Through serial deletion experiments combined with computational analyses, a 6-bp sequence was identified as a potential cis-element required for the odr-10 expression in AWA. More experiments are demanded to characterize whether it serves as the regulatory sequence functional in other AWA-expressed genes.