Provided is an arthropod pest control composition, the composition having an superior effect on control of arthropod pests. The composition comprises 0.01 to 0.5% by weight of a neonicotinoid insecticidal compound, 10 to 50% by weight of an organic solvent selected from the group consisting of monoalcohols having 1 to 3 carbon atoms and acetone, and 49.5 to 89.99% by weight of liquefied carbon dioxide, wherein the weight of ethanol to that of the neonicotinoid insecticidal compound is 100 times or more.
