This paper proposes a fast morphological algorithm for color image multi-scale segmentation based on connected sets using vertex-collapse algorithm. Color morphological operators are defined based on a special full order relation of color vectors in HSV model. Morphological opening-closing operators are implemented using vertex-collapse algorithm to form a nonlinear scale space. Both area and color are considered to calculate the similarity between adjacent regions, and entropy criterion is adopted to control the content contained in the finial scale tree. The experimental result shows that the image is segmented efficiently with perfect shape preserving.