To provide a further useful spraying agent for controlling flying insects by utilizing a specific isomeric mixture of 2-methyl-4-oxo-3-(2-propinyl)-2-cyclopenten-1-yl 2,2-dimethyl-3-(2,2-dichlorovinyl)cyclopropane carboxylate and also in considering an economical cost.

This spraying agent for controlling the flying insects contains (d)-2-methyl-4-oxo-3-(2-propinyl)-2-cyclopenten-1-yl (d)-cis, trans-2,2-dimethyl-3-(2,2-dichlorovinyl)cyclopropane carboxylate as an active ingredient, and has the 5 to 50% relative amount of the cis-form in the ester compound of the active ingredient and also the 50 to 95% relative amount of the trans-form.