Improved structure of bicycle warning device

An improved structure of a bicycle warning device mainly comprises an electric illuminant device and a power supply device, and the electric illuminant device and the power supply device are arranged on the bicycle, wherein the electric illuminant device is arranged behind of the bicycle cushion or a pole body, the pole body can be the front fork or the rear fork, and the electric illuminant device in the utility model is in a flake form, whose profile can present a plate outline, a arrow-head outline or a character outline; the power supply device is arranged near to the handlebar of the bicycle, the power supply device is equipped with a three-stage shift switch, and the shift switch provides the effects such as starting the electric illuminant device, shutting down the electric illuminant device and making the electric illuminant device to produce a flash light source and so on; in this way, the utility model can overcome the drawbacks of the prior bicycle warning device that the structure is weak, the uti