The invention relates to an insecticidal composition containing spinetoram and monosultap, and also relates to a control method of snout moth's larva. The insecticidal composition containing spinetoram and monosultap monosultap is characterized by comprising the active ingredients of spinetoram and monosultap in a weight ratio of 1:900-1:1. The insecticidal composition comprises 0.1-10 wt% of spinetoram, 40%-90 wt% of monosultap and the balance of additives. The invention also provides a control method of arthropod animal pests, especially insects, arachnids and Nematoda; and the method comprises acting the insecticidal composition containing spinetoram and monosultap on reproduction materials of target useful plants, target harmful creatures and target useful plants. The plant propagation materials comprise seedlings, roots, nursery seedlings, cuttings and seeds. In the present invention, the spinetoram and monosultap can be applied separately, sequentially or simultaneously.