An imaging apparatus includes an automatic exposure control unit that changes an exposure value based on luminance detected by a luminance detection unit for detecting luminance of an imaging screen, and a luminance changing amount detection unit that detects a luminance changing amount in the imaging screen. A method of setting an exposure value is changed between when the luminance changing amount detected by the luminance changing amount detection unit exceeds a preset luminance changing amount and when the luminance changing amount does not exceed the preset luminance changing amount.