An illumination device includes a nozzle, a grip, at least one light element connected to the nozzle, and a moveable turbine generator electrically connected to the light-emitting element. The turbine generator includes at least one rotatable blade. When the turbine generator is moved into the nozzle, the impact of a fluid flowing through the nozzle causes the rotatable blade to rotate, thereby generating electric power to power the light-emitting element. When the turbine generator is moved into the grip, the rotatable blade is not subjected to the impact of the fluid flowing through the nozzle, stopping the turbine generator from generating the electric power.