() is important for sex differentiation in the model organism . In our previous study, the basic molecular characteristics of the gene () in (Henri Milne Edwards, 1854) were cloned to determine the relationship with sex differentiation. In this study, the genomic sequence of contained five exons and four introns, with an exceptionally long 3'UTR sequence. The qRT-PCR results of demonstrated lower tissue expression in the androgenic gland of the intersex crab than the normal male crab, implying that plays a role in crab AG development. RNA interference experiments and morphological observations of juvenile and mature crabs indicated that influences sexual development in . A dual-luciferase reporter assay disclosed that tcf-miR-315-5p effectively inhibits the translation of the gene, influencing male development. An intriguing finding was that miRNA tcf-miR-307 could increase expression by binding to the alternative splicing region with a length of 248 bp (ASR-248) in the 3'UTR sequence. The present research contributes to a better understanding of the molecular regulation mechanism of and provides a resource for future studies of the miRNA-mediated regulation of sexual development and regulation in .