An image capturing device and an image capturing system are provided. The image capturing device includes an optical system, a first filter provided near a diaphragm position of the optical system, a sensor, and a lens array. The first filter includes a plurality of filters respectively having different spectral characteristics. The sensor includes a plurality of filters respectively having different spectral characteristics. The lights from an object pass through the respective filters of the first sensor and the respective filters of the second sensor to simultaneously form a plurality of types of spectral image of the object on an image plane of the sensor.