1. A method for extracting salient object from stereoscopic video comprising the steps of: (A) dividing regions based on the similarity of color and distance between pixels in a left-eye image and a right-eye image from an input stereoscopic image; (B) creating a disparity map of divided regions based on a disparity obtained from a pixel difference of the left-eye image and the right-eye image; (C) calculating a contrast-based saliency by comparing the regions in the step (A) and the divided regions of the disparity map in the step (B); (D) calculating a prior-knowledge-based saliency based on a prior-knowledge for the regions in the step (A) and the divided regions of the disparity map in (B) step, the prior-knowledge being comprised of features of the image being visually distinct; and (E) extracting salient regions of the image based on the contrast-based saliency and the prior-knowledge-based saliency.