Formula (1) [In the formula, G1 represents a nitrogen atom or the like, G2 represents a nitrogen atom or the like, A1 represents a nitrogen atom or the like, A2 represents a nitrogen atom or the like, A3 represents a nitrogen atom or the like, and A4 represents Represents a nitrogen atom, A5 represents a nitrogen atom, R1 represents a C1-C6 chain hydrocarbon group optionally having one or more atoms or groups selected from group X, R2, R3 And R4 are the same or different and each represents a C1-C6 chain hydrocarbon group which may have one or more atoms or groups selected from group X, R5 and R6 are the same or different, and group X Represents a C1-C6 chain hydrocarbon group or the like which may have one or more atoms or groups selected from the above, and n represents 0, 1 or 2. ] The condensed heterocyclic compound shown by this, or its N-oxide has the outstanding pest control effect.式（１）〔式中、Ｇ１は窒素原子等を表し、Ｇ２は窒素原子等を表し、Ａ１は窒素原子等を表し、Ａ２は窒素原子等を表し、Ａ３は窒素原子等を表し、Ａ４は窒素原子等を表し、Ａ５は窒素原子等を表し、Ｒ１は群Ｘより選ばれる１個以上の原子若しくは基を有していてもよいＣ１－Ｃ６鎖式炭化水素基等を表し、Ｒ２、Ｒ３及びＲ４は同一又は相異なり、群Ｘより選ばれる１個以上の原子若しくは基を有していてもよいＣ１－Ｃ６鎖式炭化水素基等を表し、Ｒ５及びＲ６は同一又は相異なり、群Ｘより選ばれる１個以上の原子若しくは基を有していてもよいＣ１－Ｃ６鎖式炭化水素基等を表し、ｎは０、１又は２を表す。〕で示される縮合複素環化合物、又はそのＮ－オキシドは優れた有害生物防除効果を有する。
