Abstract:The joint action of the mixtures of chlorpyrifos, emamectin benzoate, chlorantraniliprole and abamectin were studied on Chilo suppressalis Warker. The results showed that when the ratio of chlorpyrifos to emamectin benzoate was 1∶1, chlorpyrifos to chlorantraniliprole was 10∶1, abamectin to chlorantraniliprole was 1∶1 and abamectin to chlorpyrifos was 1∶1, the co-toxicity coefficient (CTC) of the mixtures were the maximum. The CTC were 376.77, 254.84, 247.10 and 682.34 respectively. The field trials showed that these mixtures could control C.suppressalis effectively, the control effect were all above 76.4%, and the mixtures were safety to the rice.