An imaging apparatus for recording image data picked up by an image pickup unit until a recording medium is presented. In response to an instruction from an instruction operation unit capable of arbitrary instruction, a first image data picked up by the image pickup unit is allocated to the same group as a second image data photographed immediately before the first image data so as to allocate the first image data to the same group as the image data picked up immediately before the first image data. In addition, management information containing group information that shows image data within the group is generated.