There is a harmful organism that cannot be controlled or is difficult to be controlled with the use of a single agent of a compound represented by the general formula (1) according to the invention, an insecticide, a miticide or a bactericide. Accordingly, an object of the invention is to provide a composition for preventing harmful organisms for efficiently controlling such a harmful organism.That is, the invention is directed to a composition for preventing harmful organisms, characterized by comprising the compound represented by the general formula (1) and other insecticides, miticides or bactericides as active ingredients,wherein, in the formula, A1, A2, A3 and A4 independently represent a carbon atom, a nitrogen atom or an oxidized nitrogen atom G1 and G2 independently represent an oxygen atom or a sulfur atom R1 and R2 independently represent a hydrogen atom or a C1 to C4 alkyl group Xs may be the same or different and represent a hydrogen atom, a halogen atom or a trifluoromethyl group Q1 represents a substituent such as a phenyl group or a heterocyclic group and Q2 represents a substituent such as a phenyl group or a heterocyclic group.)
