The invention provides a highway crossing device for a wire. The highway crossing device comprises bottom plates (12), counter weights, vertical support rods (11), telescopic rods (5), transverse support rods (4) and a plurality of U-shaped bracket (1). The highway crossing device is characterized in that each counter weight is arranged on each bottom plate (12); the lower end of each vertical support rod (11) is fixedly connected to one side of each bottom plate (12); each telescopic rod (5) is arranged at the upper end of each vertical support rod (11); the upper end of each telescopic rod (5) is connected with the middle part of each transverse support rod (4); the plurality of U-shaped brackets (1) are arranged on each transverse support rod (4) at intervals to form a set of support mechanism for the wire (14); two sets of support mechanisms are placed at two sides of the highway respectively; and the wire (14) is located on the U-shaped brackets (1) on the transverse support rod (4) of two sets of support mechanisms. The support mechanisms can be stably located at two sides of the highway through the counter weights; and the wire is kept far away from the highway pavement by the U-shaped brackets on the transverse support rods, so that a wire hanging accident of a vehicle is avoided.