A scanning endoscope apparatus includes: a light source； first and second polarization sections； third and fourth polarization sections； a first wavelength separation section； a second wavelength separation section； a first detection section； and a second detection section. The scanning endoscope apparatus further includes: a first judgment section comparing light intensities of at least two of the light having a first wavelength band transmitted through the first wavelength separation section, the light having a second wavelength band transmitted through the first wavelength separation section, the light having the first wavelength band transmitted through the second wavelength separation section and the light having the second wavelength band transmitted through the second wavelength separation section to observe the return light on a surface area； and a second judgment section comparing light intensities of two which are not used by the first judgment section to observe the return light in a deep-part area of the subject.
