While it is more and more popular for obtaining and manipulating digital image,digital image forensics is more and mor e important in the field of mulimedia information security.This task can be cruc ial when images are used as evidence to influence or decide judgment such as in a court of law.Aiming at copy-move forgery,which is the most popular tampering method,many detecting methods have been proposed by researchers all over the wor ld.But these methods seldom take the new compression standard-JPEG 2000into ac count,which will be more and more popular.Based on this,a robust detecting metho d based on ridgelet transform is proposed in this paper.The method is according to the fact that ridgelet transform applies wavelet transform on the slices gain ed from Radon transform.Copy-move forgery detecting methods using Radon transfo rm have already been proposed and proved to be robust to some kinds of attacks e xcept JPEG 2000.The experiments done with eleven types of digital images show th at the proposed method is a robust to attackes,such as rotation,JPEG compression ,adding noise.Especially,the method is robust to the new compression standard of JPEG 2000.