The invention belongs to the image processing technical field, and concretely relates to a panorama sea-sky-line extraction method based on an improved active contour model. The method comprises the step of: (1) setting an initial contour; (2) using a Sobel operator to calculate each pixel point gradient value; (3) eliminating panorama equipment zone interference; (4) constructing an improved active contour model; and (5) iteratively extracting a sea-sky-line through a rapid greedy algorithm. Through processing means such as separation of panorama equipment zone interference, the method eliminates the adverse effects of panorama equipment zone imaging on sea-sky-line detection; and then by utilizing the oval shape of a sea-sky-line, a shape energy bound term is constructed and added to the active contour model to be used as a new energy function, thereby allowing a movable contour to restrict a contour shape in a convergence process so as to successfully converge to a panorama sea-sky-line. The panorama sea-sky-line extraction method can realize accurate extraction of an oval sea-sky-line in a panoramic visible light image on a complex sea and atmosphere background under different sea conditions and weather conditions.