The invention provides a projector, a color wheel protection circuit, and a color wheel protection method. The projector includes a color wheel, a light source, a controller, and a protection circuit. The light source is controlled by a light source control signal to provide an illumination beam to the color wheel. The controller is used for providing the light source control signal to the light source. The protection circuit includes a resetting signal generator and a logic operator. The resetting signal generator is used for generating a resetting trigger signal according to the rotation speed of the color wheel, and generating a resetting output signal according to the resetting trigger signal. The logic operator is used for receiving the light source control signal and the resetting output signal, and resetting the light source control signal according to the resetting output signal.