In　recent　years,　wildfires　have　occurred　frequently,　and　large-scale　wildfires　may　lead　to　transmission　line　tripping　accidents.　To　accurately　obtain　the　real-time　location　of　wildfires,　alarm　in　advance,　and　predict　the　trip　probability　of　the　transmission　line　accurately,　this　paper　proposes　a　real-time　transmission　line　tripping　probability　calculation　method　considering　the　spread　of　wildfires.　On　the　one　hand,　cellular　automata　are　used　to　simulate　the　spread　of　wildfires,　and　real-time　warning　levels　are　obtained.　On　the　other　hand,　according　to　the　breakdown　mechanism　of　the　air　gap,　the　real-time　change　trend　of　the　probability　of　wire　tripping　is　calculated　from　the　critical　distance.　The　research　results　show　that　the　proposed　method　can　accurately　and　effectively　calculate　the　warning　level　and　tripping　probability　of　transmission　lines　caused　by　wildfires,　which　is　of　great　reference　value　for　emergency　response　of　power　grids　under　wildfire　disasters.　©　2023　IEEE.