A scanning device with multiple LED light sources and an application thereof. The scanning device includes a housing, a chassis, a main LED light source and an auxiliary LED light source. A horizontal plane of the housing is connected to a sloped plane of the housing to form a connecting section. The main LED light source has a length extending in a longitudinal direction substantially perpendicular to a moving direction of the chassis. The main LED light source provides a main light ray to illuminate the horizontal plane, and includes a first circuit board mounted on the chassis and first LEDs mounted on the first circuit board. The auxiliary LED light source includes a second circuit board mounted on the chassis and a second LED mounted on the second circuit board. The second LED provides an auxiliary light ray to illuminate the connecting section.