An endoscope apparatus has: a light source device that includes a light source irradiating narrow band light and a fluorescent substance to emit predetermined fluorescent light and that irradiates illumination light an endoscope body that includes an imaging element outputting an image signal and a processing device that includes a signal dividing unit dividing the image signal into a first image signal corresponding to the narrow hand light and a second image signal corresponding to the fluorescent light, a blood vessel depth information calculating unit calculating blood vessel depth information based on the first image signal and the second image signal, a spectral estimation information calculating unit calculating spectral estimation information based on the second image signal, and an image processing unit generating a captured image from the first image signal, the second image signal, the blood vessel depth information, and the spectral estimation information.