PROBLEM TO BE SOLVED: To provide a harmful beast intrusion prevention system capable of allowing a pedestrian or an automobile to smoothly pass through the passage while preventing a harmful beast from entering through the passage of an electric fence. An electric fence (12) for partitioning a harmful beast habitat area (YA) and a protected area (HA) is provided. The electric fence 12 has a passageway 14 for passing the inside and outside passageway ND, and a gate device 16 is installed at the passageway 14. The gate device 16 includes a first passerby detection device 20 that can detect a person approaching the passageway 14 from the harmful beast habitat area YA side by distinguishing it from a harmful beast. A second passerby detection device 22 capable of detecting a harmful animal approaching the passageway 14 from the harmful animal habitat area YA side is provided. A third passerby detection device 24 capable of detecting a person approaching the passport 14 from the protected area HA side is provided. A repellent stimulus launching device 26 is provided for firing the repellent stimuli S1, S2, S3 disliked by the harmful beasts to the harmful beasts approaching the passage 14 and driving the harmful beasts to the harmful beast habitat area YA side. [Selection diagram] Fig. 3【課題】有害獣が電気柵の通行口から侵入するのを防止しつつ、歩行者や自動車が通行口をスムーズに通行できる有害獣侵入防止システムを提供する。【解決手段】有害獣生息エリアＹＡと保護エリアＨＡとを区画する電気柵１２を備える。電気柵１２は、内外通行道路ＮＤを通すための通行口１４を有し、通行口１４にゲート装置１６が設置される。ゲート装置１６は、有害獣生息エリアＹＡ側から通行口１４に近づく人間を、有害獣とは区別して検出可能な第１の通行者検出装置２０を備える。有害獣生息エリアＹＡ側から通行口１４に近づく有害獣を検出可能な第２の通行者検出装置２２を備える。保護エリアＨＡ側から通行口１４に近づく人間を検出可能な第３の通行者検出装置２４を備える。通行口１４に近づいた有害獣に対し、有害獣が嫌がる忌避刺激Ｓ１，Ｓ２，Ｓ３を発射して有害獣を有害獣生息エリアＹＡ側に追い払う忌避刺激発射装置２６を備える。【選択図】図３
