Abstract: The present invention provides a means for regulating (promoting or suppressing) the growth of Decapoda crustaceans such as shrimps and crabs. Methods of the present invention regulate the growth of animals belonging to the Decapoda, comprising a step of regulating (inhibiting or enhancing) the function of genes comprising: at least one growth regulation-related gene selected from the group consisting of mTOR pathway, Akt pathway, and upstream and downstream factors of the pathways; and further optionally at least one molting-related gene selected from a molting-related factor or the function of a transcription or translation product of the genes.