Safety　of　electricity　transmission　tower-line　systems　is　always　at　risk　from　various　natural　hazards,　especially　typhoons,　which　have　the　potential　to　cause　significant　damage　and　disruption.　However,　previous　studies　have　predominantly　focused　on　typhoons　occurring　in　open-flat　terrains,　disregarding　the　impact　of　actual　terrains.　To　address　this　research　gap,　this　paper　comprehensively　examines　the　typhoon-induced　responses　of　an　electricity　transmission　towerline　system　while　considering　the　influence　of　microtopography.　Specifically,　a　virtual　wind　tunnel　is　first　established　to　simulate　the　typhoon　within　a　specific　microtopography.　The　wind　characteristics　of　the　typhoon　considering　the　influence　of　microtopography　are　then　studied　in　terms　of　the　average　wind　speed,　gust　factor,　and　turbulence　intensity,　and　compared　to　those　at　open-flat　terrains.　Finally,　the　influences　of　microtopography　on　the　typhoon-induced　responses　and　collapse　of　the　electricity　transmission　tower-line　system　are　investigated.　The　results　demonstrate　that　the　introduction　of　microtopography　can　obviously　increase　local　wind　speed　and　enhance　fluctuation　of　wind,　resulting　in　large　responses　and　collapse　risk　of　electricity　transmission　tower-line　systems.　This　paper　could　provide　a　valuable　reference　for　assessing　the　wind-resistant　capacity　of　electricity　transmission　lines　located　in　complex　terrains,　e.g.,　mountains　and　valleys.