1. A vehicle tracking method, comprising the steps of: capturing a plurality of bright objects from an image by the bright object segmentation; labeling coordinates of the plurality of bright objects by a connected component object labeling method to form a plurality of connected component objects; identifying, analyzing and combining characteristics of the plurality of connected component objects by the bright object recognition to form a plurality of lamp objects; and identifying the type of a vehicle having the plurality of lamp objects by vehicle detection/recognition, and counting the number of various vehicles; wherein the bright object recognition respectively compares values of the aspect ratio, area and density of the plurality of connected component objects with a maximum aspect ratio threshold value, a minimum aspect ratio threshold value, a maximum area threshold value, a minimum area threshold value and a density critical threshold value to determine the characteristics of the plurality of connected component objects to capture the plurality of lamp objects; and if the bright object recognition determines that any two of the connected component objects have a horizontal distance and a vertical distance smaller than a horizontal distance threshold value and a vertical distance threshold value respectively, then the paired connected component objects are combined to form a lamp object.