The fused heterocyclic compound represented in formula (1) has excellent effectiveness in pest control. (In the formula, A1 represents -NR4-, etc., A2 represents a nitrogen atom, etc., R1 represents an ethyl group, a cyclopropyl group, or a cyclopropylmethyl group, R2 represents -S(O)mR6 or -C(R7)(CF3)2, R4 represents a C1-C6 alkyl group optionally having one or more halogen atoms, R6 represents a C1-C6 haloalkyl group, R7 represents a fluorine atom or a chlorine atom, and m and n each represents 0, 1 or 2.)
