An imaging apparatus includes an imaging device that photoelectrically converts an optical image obtained through a focus lens. The focus lens is moved to a focus position set by focus detection performed based on image signals from the imaging device with a first aperture value. A first correction amount of the set focus position is acquired according to a difference between the first aperture value and a second aperture value to be used at a time of photographing. Photographing is executed at a determined focus position at the time of photographing, by a user's operation. If the first correction amount is larger than a predetermined amount, a focus position corrected according to the first correction amount is determined as the focus position at the time of photographing, and if not, the set focus position is determined as the focus position at the time of photographing.