An imaging apparatus including an image sensor, an evaluation value calculation unit, and an in-focus position calculation unit. The image sensor performs photoelectric conversion on a subject image formed by an image optical system including a focus adjustment unit. The evaluation value calculation unit calculates a first and a second focus evaluation values with spatial frequency components of first and second frequency bands extracted from image signals output from the image sensor. The second frequency band includes a spatial frequency component higher than the spatial frequency component of the first frequency band. The in-focus position calculation unit defines a position at which a third focus evaluation value reaches its peak value as an in-focus position of the focus adjustment unit. The third focus evaluation value is obtained by calculating a ratio of the first and the second focus evaluation values.