Provided are a focusing position determining apparatus, an imaging apparatus, and a focusing position determining method, the method including setting an aperture to a first aperture value; driving a focus lens through a first range of positions as a first drive; during the first drive, obtaining images periodically, and calculating a first sampling of contrast values from the obtained images; calculating a first focus position from the first sampling of contrast values; setting the aperture to a second aperture value; driving a focus lens through a second range of positions as a second drive, the second range of positions being based on the first focus position; during the second drive, obtaining images periodically, and calculating a second sampling of contrast values from the obtained images; calculating a focusing position from the second sampling of contrast values; and driving the focus lens to the calculated focusing position.