An apparatus for detecting a camera tampering, includes: an image capturing unit to capture at least one image; an input-edge-image generating unit to extract an edge image from an object displayed in the captured image and generate an input edge image by using the extracted edge image; a reference-edge-image generating unit to generate a reference edge image from the input edge image; a stolen-edge-image generating unit configured to generate a stolen edge image by substracting the input edge image from the reference edge image; and a tampering determining unit to compare the input edge image with the reference edge image, compare the reference edge image with the stolen edge image, and determine whether or not a camera tampering has occurred, based on a first similarity and a second similarity.