In a previous study, three larval cuticle protein genes were cloned from the mulberry longicorn beetle, Apriona germari (Comp. Biochem. Physiol. B 136, 803-811, 2003). In the present study, the genomic structures of these three larval cuticle protein genes (AgLCP9.2, AgLCP12.6 and AgLCP12.3) were elucidated. All three cuticle protein genes consist of one intron and two exons. Southern blot analysis of genomic DNA suggested that three cuticle protein genes are a single copy gene. In addition, a novel larval cuticle protein gene, AgLCP10.6, was cloned from A. germari in this study. The AgLCP10.6 cDNA contains an ORF of 300 nucleotides that are capable of encoding a 100-amino acid polypeptide with a predicted molecular mass of 10.6 kDa. The amino acid sequence deduced from the AgLCP10.6 cDNA contained a type-specific consensus sequence identifiable in other insect cuticle proteins and is most homologous to Drosophila melanogaster cuticle protein ACP65A (51 % protein sequence identity). Northern blot analysis revealed that AgLCP10.6 showed epidermis-specific expression.