Interframe and intraframe copy-paste forgery are two typical video forgery means. Interframe manipulation is easily done with the video editing software. An algorithm based on nonnegative matrix factorization(NMF) and speed-up robust featuare(SURF) is proposed for detecting interframe copy-paste forgery. Frames are transformed via wavelet．And low-frequency band is further decomposed by NMF. The NMF coefficient matrix is served as the video frame feature descriptor. The variation of frame similarity is used for locating the forged first and last frames via measuring frame similarity. The starting and ending frames mark the suspicious frame sequence, and these frames are further investigated by SURF. The presented approach avoids frame-by-frame match and decreases the time complexity to O(n). The experiment demostrates that the proposed algorithm performs well for interframe video copy-paste forgery detection.