Bipyridine compound that has excellent efficacy in controlling harmful arthropods. A composition comprising the same. Claim 1: A bipyridine compound represented by formula (1) or its N-oxide compound, [characterized in that R¹ represents a haloalkyl group C₂₋₁₀,a C₃₋₁₀ haloalkenyl group,a C₃₋₁₀ haloalkynyl group,a (C₁₋₅ alkoxy) C₂₋₅ alkyl group having one or more halogen atoms, a (alkylsulfanyl C₁₋₅) alkyl C₂₋₅ group having one or more halogen atoms, a (Cils alkylsulfinyl) group C₂₋₅ alkyl having one or more halogen atoms, a group (Cils-alkylsulfonyl) C₂₋₅-alkyl having one or more halogen atoms, a group (C ciclo-cycloalkyl) C₁₋₃-alkyl having one or more substituents selected from Group G, or a C₃₋₇ cycloalkyl group having one or more substituents selected from Group G； R² represents a C₁₋₆ alkyl group optionally having one or more halogen atoms,a cyclopropylmethyl group, or a cyclopropyl group； R³ represents a C₁₋₆ chain hydrocarbon group optionally having one or more substituents selected from Group B, a phenyl group optionally having one or more substituents selected from Group D, a 5- or 6-membered aromatic heterocyclic group optionally having one or more substituents selected from Group D, an OR¹²,A month agoNo. 7491； r74191；8308； 1,One nroc11 (o) R1 3,No. 8308； NR1 (o) R1 3,One nhro1 (o) or1 8308；un NR NR C (O) ORun NR C (O) NR Run NR NR C (O) NR Ran N = CHNR¹⁵R¹⁶,un N 3DS (O) R Run S (O) ROne C (o) or 8311；One C (o) NR 1,a cyano group, a nitro group, or a halogen atom； R⁶ represents a C₁₋₆ alkyl group optionally having one or more halogen atoms, an OR¹⁸,No. 8312； r8313；One C (o) or 83099,1 D (o) r83044,A Ciano group, a nitro group, o r a halogen atom； R1,R18311,R831222,R8313,830404,R²⁴ and R²⁵ independently represent one another a hydrogen atom, or a C₁₋₆ chain hydrocarbon group optionally having one or more halogen atoms； R¹² represents a hydrogen atom, a C₁₋₆ chain hydrocarbon group optionally having one or more halogen atoms, a C₁₋₆ alkyl group having a sub
