A scanning endoscope apparatus comprising: a light source section that emits illuminating light; a light guiding section that guides and applies the illuminating light to a subject from a distal end in such a manner that the illuminating light has directionality; a scanning section that performs scanning in which a direction of the distal end of the light guiding section is varied; a first light detecting section (12b, 12g, 12r) that detects light in a wavelength band of the illuminating light and detects light from a scanning range of the scanning section at the distal end of the light guiding section; a second light detecting section that does not detect light in the wavelength band of the illuminating light, but detects light in a wavelength band other than the wavelength band of the illuminating light; an illumination control section (4, 5) that controls, with a predetermined cycle, a light application period in which the illuminating light is applied from the distal end of the light guiding section and an interruption period in which the application of the illuminating light from the distal end of the light guiding section is interrupted; a removal section that corrects a result of detection by the second light detecting section in the light application period, based on a ratio of a result of detection by the first light detecting section relative to a result of detection by the second light detecting section in the interruption period to estimate an extrinsic light component contained in the result of detection by the first light detecting section in the light application period, and removes the estimated extrinsic light component to extract a return light component of the illuminating light from the subject; and an image processing section that forms an image from the return light component extracted by the removal section, based on information of the direction of the distal end of the light guiding section from the scanning section. a light source section that emits illuminating light; a light guiding section that guides and applies the illuminating light to a subject from a distal end in such a manner that the illuminating light has directionality; a scanning section that performs scanning in which a direction of the distal end of the light guiding section is varied; a first light detecting section (12b, 12g, 12r) that detects light in a wavelength band of the illuminating light and detects light from a scanning range of the scanning section at the distal end of the light guiding section; a second light detecting section that does not detect light in the wavelength band of the illuminating light, but detects light in a wavelength band other than the wavelength band of the illuminating light; an illumination control section (4, 5) that controls, with a predetermined cycle, a light application period in which the illuminating light is applied from the distal end of the light guiding section and an interruption period in which the application of the illuminating light from the distal end of the light guiding section is interrupted; a removal section that corrects a result of detection by the second light detecting section in the light application period, based on a ratio of a result of detection by the first light detecting section relative to a result of detection by the second light detecting section in the interruption period to estimate an extrinsic light component contained in the result of detection by the first light detecting section in the light application period, and removes the estimated extrinsic light component to extract a return light component of the illuminating light from the subject; and an image processing section that forms an image from the return light component extracted by the removal section, based on information of the direction of the distal end of the light guiding section from the scanning section.