This invention is to simplify operations for photographing a subject and acquiring radio tag information. In this invention, when a radio tag information registration photographing mode is selected, and it is detected that the photographing button (shutter button) is pressed halfway, a radio tag detector generates a radio wave that excites a radio tag. Whether a response from the radio tag is received is then determined. When a response is received from the radio tag, and a radio tag ID can uniquely be decided, a status "photographing OK" is indicated. When the photographing button in the half-pressed state is pressed completely, image sensing processing is executed. Radio tag information and obtained image information are stored in an information format, in which they are paired.