Because fingerprint directional image represents the basic structural feature really and abstractly, It has very important research value in automatic fingerprint identification system. Now it has been widely used to solve the problem of image enhancement, global feature extraction, automatic classification, template matching and image encoding. Especially the Gabor filter based on directional image gets a marvelous effect, which can filter the noises along ridges. Combining the author's research work, several newly developed methods to get directional image are introduced. The performance of real-time and robust to noise of these methods are assessed,and the mending methods are presented also. In the end, the typical applications are systematically overviewed and the direction for further study is provided.