A people counting system includes: a top-view, a first and a second side-view image-capturing device, capturing a top-view, a first and a second side-view image respectively; an image stitching module, stitching the top-view, the first and the second side-view image into an ultra wide-angle image; a ROI selecting module, selecting at least one recognition zone and a counting zone; a face recognition module, monitoring the recognition zone to determine a face location corresponding to a face through analyzing the recognition zone; a head recognition module, monitoring the counting zone to determine a head location corresponding to a head through analyzing the counting zone; an object tracking module, the head recognition module, generating a face track and a head track; and a people counting module, counting a first number of face tracks and a second number of head tracks passing through the counting zone and generating a counting result.