An image scanning apparatus is provided. The image scanning apparatus includes an image sensor configured to scan image information of a manuscript, a converter configured to convert a signal scanned by the image sensor into a digital signal, a processor configured to control the converter by using a plurality of control signals and perform image-processing with respect to the signal converted into the digital signal, and a reset circuit unit configured to generate a reset signal by using the plurality of control signals and provide the converter with the generated reset signal.