A novel parallel graph-based image segmentation algorithm was constructed to segment high-resolution image precisely in real time.This algorithm adopts parallel structure and divides the image into multiple regions.Parallel processing can be made to the non-adjacent regions.This algorithm can be deployed easily on multi-core processors for multi-core parallel processing to shorten the runtime.In order to segment precisely and enhance the ability in clutter scenes, this algorithm combines the smooth regions directly by setting low weight threshold.Based on this method, the object regions can be segmented coherently. Experiments demonstrate that this algorithm can segment high-resolution images rapidly and precisely, has better performance than the traditional segmentation algorithms, and can achieve high level performance in segmenting images with complex background.