Plodia interpunctella, Indianmeal moth, is world-widely distributed pest in stored and manufactured agricultural products. Practically, this species seriously damaged by the infestation of most stored and manufactured agricultural products. It is necessary to find useful techniques for the control of stored-product pests insects including P. interpunctella. Recently, heating at 55℃ for 48 h can be practically used to disinfest stored-product insects in the filed of manufactures. To improve efficiency of this technique we conducted combination treatments with heat and diatomaceous earth. At room temperature, wandering larvae, which is most tolerant developmental stage to heat, were not dead regardless of diatomaceous earth (4 mg/L) treatment within 24 h. However, incubation at 40℃, all the larvae were dead with diatomaceous earth treatment while its mortality was 28% without diatomaceous earth treatment. Thus, heating effects was significantly improved by the combined treatments of diatomaceous earth. This effect was increased when temperature was higher and the exposed time is longer. Our results clearly showed that the combined treatments of both heat and diatomaceous earth showed synergistic effects for the control of P. interpunctella.