To solve such a problem that birds stop on the electric cables or wires, since a conventional bird repellent has no moving or movable elements and the birds are on their guard at the beginning but they become habituated to it before long and stop on the cables and wires.

This bird repellent device 2 is constituted of a base body 3 firmly fixed to the wire 1 and a rotor 4 that is loosely fitted to the firmly fixed base body. Accordingly, the loosely fitted rotor 4 is freely rotatable around the firmly fixed base body 3 as the rotation center. In addition, the rotor 4 is equipped with blades in the radial direction and is made readily rotatable by the wind blow. When a bird tries to stop on the bird-repelling device, the rotor promptly is rotated by the weight of the bird and it cannot stay long on the device 2. When the wind blows, the rotor continuously rotates to always change the whole shape offensively to the birds, thereby the birds are forced to be on guard and not habituated.