The utility model provides a bird net is prevented to hirudiniculture box with a net, includes the mesh grid piece, mesh grid piece central authorities be provided with the little small bell of a plurality of, also be provided with little small bell on four angles, mesh grid piece skin scribbles fluorescent substance, it is outer that it drives the bird ball still to be provided with a plurality of all around. The utility model discloses the structure is ingenious reasonable, prevents birds pecking leech, reduces and breeds the loss.