The influence of Bacillus thuringiensis on the growth and development of Plodia interpunctella (Hübner) larva was reported in this research by applying half manual feedstuff mixed with drug. The result indicated that Bacillus thuringiensis didn′t have obvious poison effect against Plodia interpunctella (Hübner) larva.When the dosage concentration was no more than 20 000 IU/g, the Bacillus thuringiensis didn′t markedly affect the survival of Plodia interpunctella (Hübner) larva,which is similar to the contrast group at 7 days. At the same time,when the dose was no less than 2 500 IU/g,Bacillus thuringiensis.could markedly restrain the pupate and eclosion action of this pest.