Monitoring　and　alarm　play　an　important　role　in　preventing　trip-out　caused　by　wildfires　for　high-voltage　transmission　lines.　This　paper　proposes　a　multi-Doppler　weather　radar-based　method　for　monitoring　and　alerting　of　wildfires　near　transmission　lines.　Firstly,　characteristic　parameters　are　mathematically　proposed　to　distinguish　wildfire＇s　radar　echoes.　Then,　the　four-site　neighbourhood　algorithm　and　the　multithreading　method　are　used　to　extract　all　possible　wildfire　echo　units　detected　by　various　Doppler　weather　radars,　and　a　cumulative　probability　is　calculated　to　identify　the　wildfire.　Finally,　a　regional　block　search　method　is　used　to　quickly　locate　wildfire-affected　transmission　towers.　The　membership　function　of　spread　time　in　the　fuzzy　set　is　proposed　to　determine　the　alarm　level,　which　takes　into　account　the　influences　of　environment,　topography,　and　vegetation　on　wildfire　spread　rate.　The　application　to　a　provincial　power　grid　demonstrates　that　the　proposed　method　has　an　accuracy　of　82.4%,　a　missing　alarm　rate　of　27.4%,　and　a　delay　of　fewer　than　15　min.　In　addition,　the　joint　observation　of　wildfires　by　multi-Doppler　weather　radars　and　satellites　indicates　a　promising　application　prospect for　transmission　line　wildfire　fighting.　©　2023　The　Authors.　IET　Generation,　Transmission　&　Distribution　published　by　John　Wiley　&　Sons　Ltd　on　behalf　of　The　Institution　of　Engineering　and　Technology.