Pet exercise wheel assembly having light-emitting device

A pet exercise wheel assembly having a light-emitting device includes an exercise wheel made of a material pervious to light. The exercise wheel has a tapered sleeve projecting from a center of the exercise wheel and is axially formed with a penetrating channel. A light-emitting device has a casing coupled to the tapered sleeve of the exercise wheel. The light-emitting device has a circuit board formed with a central hole and provided with at least a lamp, a battery, a rocker switch, and an IC chip that are electrically connected with each other, with the lamp exposed at an exterior of the casing. Thereby, rotation of the exercise wheel drives the light-emitting device to rotate, so that the rocker switch in the light-emitting device is rocked to close a loop of the circuit board, thus causing the lamp to blink and provide a visual entertaining effect.