Abstract: In order to scientifically apply insecticides to control the potato tuber moth Phthorimaea operculella (Zeller), the toxicities of five insecticides to eggs and larvae of potato tuber moth were tested in laboratory. The results showed that the descending order of toxicity of these five insecticides to eggs of potato tuber moth was cyhalothrin, decamethrin, emamectin benzoate, beta cypermethrin, fenvalerate. The results showed that the descending order of toxicity of these five insecticides to larvae of potato tuber moth was cyhalothrin, decamethrin, beta cypermethrin, fenvalerate, emamectin benzoate. In the controlling of this pest, cyhalothrin and decamethrin should be adopted.