An image projection device includes a projection component, a photodetector, and a determination component. The projection component is configured to project an image by scanning light beams two-dimensionally. The photodetector is configured to detect reflected lights obtained in response to the light beams being reflected by a reflecting object. The determination component is configured to determine whether or not the reflecting object is an input object based on whether or not a difference of light detection positions of the light beams is at least a specific value. The light detection positions are indicative of irradiation positions of the light beams in a projection region of the image, respectively.