PURPOSE:To provide an insecticidal composition for Lissorhoptrus oryzophilus, containing ethylthiometon in combination with BPMC, NAC or carbosulfan, exhibiting remarkable synergistic effect which cannot be attained by separate use of the component and capable of keeping the insecticidal activity over a long period. CONSTITUTION:The objective insecticidal composition for Lissorhoptrus oryzophilus is produced by compounding (A) 0,0-diethyl S-[2-(ethyl) ethyl]phosphorodithioate (abbreviated as ethylthiometon) and (B) 2-sec- butylphenyl-N-methylcarbamate (MPMC), 1-naphthyl-N-methylcarbamate (NAC) or 2,3-dihydro-2,2-dimethyl-7-benzo[6]-furanyl-dibutylaminothio-N-methylc arba mate (carbosulfan) preferably at a weight ratio of 1:(0.5-2). An effective labor- saving controlling agent can be produced by mixing the composition with other insecticide, fungicide, herbicide, etc.