The present inventors conducted a similarity search of the amino acid sequence of known G protein-coupled receptor proteins in GenBank, and obtained a novel human GPCR gene "BG37". cDNA containing the ORF of the gene was cloned and its nucleotide sequence was determined. Moreover, novel GPCR "BG37" genes from mouse and rat were isolated. Use of the novel GPCR of the present invention enables screening of ligands, compounds inhibiting the binding to a ligand, and candidate compounds of pharmaceuticals which can regulate signal transduction from the "BG37" receptor.