White leg shrimp Litopenaeus vannamei is a prime aquaculture species, and it covers 90% of western hemisphere culture and is also extensively farmed in Asia. The estimated annual production from Asia during 2002 was 316000 mt. In China, exotic species (L. vannamei) had introduced during 1988 for experimental purposes and by 1998 is being successfully cultured in commercial scale; over 1000 hatcheries are in operation. The 300000 tons and 210000 tons harvested during 2003 in marine and freshwater farming respectively. To give more understanding for the white leg shrimp, we have investigated the genesis of important systems and organ, including digestive system, nervous system and haematopoetic tissue, furthermore dealed with two important immune related genes.