The utility model discloses a river transmission line warning device strides, including being used for detecting the level switch and the display of water level, the display is installed on transmission line's shaft tower 1, and level switch installs in the river, and level switch passes through the input ports are connected of cable and display, be provided with calculation module and water level acquisition module in the display, level switch water level signal is gathered to the water level acquisition module, and calculation module calculates the high information display that obtains allowwing to pass through on water level acquisition 0 according to striding height of water level that river transmission line highly subtracts the collection of water level acquisition module and striding river transmission line safety height. The utility model discloses ensure large -scale sand ship, the transport ship safety passage of adopting, prevent the electric line tripping operation and stride river transmission line to crack up and the casualties.