1. A system for monitoring dynamic stability of a micro machine, comprising: an image-capturing device for capturing images of a micro tool of the micro machine processing on a workpiece; and an analysis device, comprising: an image input interface for receiving the images captured by said image-capturing device; means for transforming the images into gray-level to gray-levelized images; means for analyzing abnormal gray-level ratio of the gray-levelized images; and means for calculating vein quantity of the gray-levelized images.