DT grid is a powerful algorithm use for analyze discrete points in the mathematics. So that, DT grid is use for solve the problem of the geology but now it is use for solve the problem of fingerprint too. In this paper, we make some improve based on the traditional DT grid. Although this algorithm is not better than the traditional DT grid at the accuracy of the distinguish, but it uses less time because it uses the feature of fingerprint is not easy to change. If it use in the big database, the superiority of this algorithm is very obvious.