The invention provides an automatic batch extraction method for horizontal vector contours of buildings in satellite images. The method comprises the steps of firstly using a K-means algorithm to class the images to obtain the backbone parts of the buildings, and solving the problem of selection of initial seed points by taking mass centers of all building areas; after the areas of all the seed points are grown, separating the building areas from surrounding areas by virtue of image edge information and removing non-building areas according to characteristic parameters such as rectangularity and strip index to realize the automatic extraction of the horizontal pixel contours of the buildings; then using techniques such has Hough transformation and block processing to perform linear vector processing to the horizontal pixel contours, and finally obtaining the horizontal vector contours of all buildings in a batch. The automatic batch extraction method for the horizontal vector contours of the buildings in the satellite images is applicable to the batch and quick extraction of the horizontal vector contours of common polygonal buildings with top views which are of straight-line segment structures in the satellite images.