Provided is an imaging apparatus that captures a multispectral image of four bands or more. An imaging apparatus (1) includes an imaging optical system (10), an image sensor (100), and a signal processing unit (200). The imaging optical system (10) includes a bandpass filter unit (16) of which at least one of aperture regions transmits light beams of a plurality of wavelength ranges, and a polarization filter unit (18) that polarizes the light beams transmitted through the bandpass filter unit (16) in a plurality of directions, in a vicinity of a pupil thereof. The image sensor (100) receives light beams transmitted through a plurality of types of spectral filter elements and a plurality of types of polarization filter elements. The signal processing unit (200) processes signals output from the image sensor (100) to generate a plurality of image signals. In the imaging apparatus (1), the number of transmission wavelength ranges of at least one of the aperture regions of the bandpass filter unit (16) is equal to or less than the number of transmission wavelength ranges of the spectral filter element.