A new digital image scrambling method based on Fibonacci numbers is presented. The uniformity and periodicity of the scrambling transformation are discussed. Our scrambling transformation has the following advantages: (1) encoding and decoding is very simple and they can be applied in real-time situations (2) the scrambling effect is very good, the information of the image is re-distributed randomly across the whole image; and (3) the method can endure common image attacks, such as compression, noise and loss of data packet.