An object of the present invention is to provide an automatic focusing apparatus which can reduce the time required to detect focused position in accordance with the operating environment by adjusting the voltage applied to a liquid crystal lens. The apparatus includes a liquid crystal lens whose focal length varies with an applied voltage, a liquid crystal lens driving unit which applies a prescribed voltage to the lens, an optical-to-electrical converter which produces an image signal from an optical image passed through the lens, a temperature sensor which detects temperature near the lens, and a control unit which extracts a plurality of focus signals by adjusting the prescribed voltage and controlling the driving unit based on the temperature or on the image signal acquisition period of the converter, and which controls the driving unit based on the extracted plurality of focus signals so that a maximum focus signal is achieved.