[Problem] To provide a method for producing an organic fertilizer in which livestock excreta is processed by house flies, Boettcherisca peregrina, and Stratiomyidae larvae, and for producing feed using matured larvae as feed for cultured fish and poultry. [Solution] A system for producing an organic fertilizer from the waste of livestock using house flies, Boettcherisca peregrina, and Stratiomyidae larvae, and for producing feed using matured larvae as feed for cultured fish and poultry, multiple cultivation processing housing units being provided for cultivating larvae or larvae hatched from eggs, and when larvae are caused to move on to a different cultivation processing housing unit in the course of the cultivation of the larvae, a movement means being used in which only the larvae are forced to move, causing the larvae to move on their own.
