Abstract: We cloned the ORF and 3'UTR of PmCFSH Crustacean female sex hormone (CFSH) gene of Penaeus monodon by RACE (Rapid-amplification of cDNA ends) method. It encodes a protein of 214 aa which contains a signal peptide and an interleukin 17E (IL-17E) domain relating to immune response. The qRT-PCR results showed that PmCFSH was expressed in various tissues, among which the highest expression level was found in the abdominal nerve tissue. The expression level gradually increased from fertilized egg stage to larval stage, and reached the maximum at larval stage. During the ovarian development Stage II to IV, it gradually increased as the ovary matured. Both Gram-negative and positive bacteria could increase the PmCFSH expression which was maximum in gill at 3^rd hour after Vibrio harveyi infection and 12^th hour after Staphylococcus aureus stimulation, while that in hepatopancreas reached the maximum at 3^rd hour after V. harveyi infection and 48^th hour after S. aureus stimulation. The study reveals that PmCFSH gene not only participates in the regulation of larval development and gonad maturity, but also has an immune response to bacterium, reflecting the "multifunction" of hormones.