An exemplary dust removing apparatus applicable for removing dust or dirt from a surface of an optical lens is provided. The dust removing apparatus includes an ultrasonic oscillation device, at least a dust removing device, and a tray. The ultrasonic oscillation device is configured for causing an ultrasonic vibration of the optical lens so as to weaken an adhesive force between the optical lens and the dust on the surface thereof. The dust removing device is configured for removing the dust from the surface of the optical lens. The tray is disposed on the ultrasonic oscillation device and located between the ultrasonic oscillation device and the dust removing device. The tray is configured for supporting the optical lens. A dust removing method is also provided.