An endoscope apparatus of the invention includes: an endoscope including an objective optical system capable of changing an observation magnification a light source device capable of selectively emitting broadband light including a visible light region and narrow-band lights of a plurality of wavelength bands obtained by discretizing light in the visible light region an observation magnification changing instruction section for issuing a magnification changing instruction for gradually increasing or decreasing the observation magnification of the objective optical system and a mode switching section for switching the light emitted from the light source device from one light to another light when detecting that the observation magnification gradually changes to reach a predetermined observation magnification based on the magnification changing instruction.
