To provide an endoscope apparatus in which the observation image can be varied continuously as the observation magnification is varied by a zoom magnification varying manipulation so that an observation image suitable for an endoscope diagnosis is obtained at each observation magnification, and to thereby prevent the operator from feeling uncomfortable and increase the accuracy of a diagnosis. An endoscope apparatus is equipped with illuminating unit having plural light sources which generate light beams having different spectra, for illuminating an observation subject; imaging unit for imaging the observation subject; observation magnification varying unit for varying observation magnification of the imaging of the imaging unit; and light quantity ratio varying unit for continuously varying an emission light quantity ratio between the plural light sources according to the observation magnification that is set by the observation magnification varying unit.