Abstract: With the development of the Internet technique, communication privacy and the information security are attracting a lot of attention recently. In this paper, the development of image encryption techniques is surveyed. Some techniques, such as pixel permutation technique, image secret segmentation technique, image secret sharing technique, and modern cryptography mechanism-based and chaotic dynamics-based image encryption techniques, are illustrated. The principles and characteristics of the corresponding technique are clarified; the analyses and comparisons are given; and the advantages, disadvantages and applied limitations are pointed out. Finally, the future direction in this field is discussed.