An illumination module including a light emitting element, a wavelength conversion unit, a control unit, and a determining unit is provided. The light emitting element is capable of emitting an excitation light beam. The wavelength conversion unit is disposed on a transmission path of the excitation light beam for converting the excitation light beam into a color light beam. The control unit is connected to the wavelength conversion unit and capable of driving the wavelength conversion unit to rotate and to shift relative to the excitation light beam. The determining unit is electrically connected to the control unit. When the determining unit determines that a shifting condition is satisfied, the determining unit instructs the control unit to shift the wavelength conversion unit relative to the excitation light beam, so as to change the irradiation position of the excitation light beam on the wavelength conversion unit.