In recent years, chaotic image encryption based on color images has been widely studied. However, in most articles, chaotic sequences generated by one chaotic system is used, and the obtained chaotic sequences will have the problem of correlation. At the same time, when using DNA technology for image encryption, the DNA operation rules are independent of the key type. In this paper, two hyperchaotic systems and new DNA operation rules are proposed for image encryption. Firstly, the improved Arnold scrambling algorithm is adopted in the scrambling process, which enhances the complexity of the scheme. Secondly, in the diffusion process, dynamic DNA coding and dynamic DNA operation addition, subtraction, XOR and mutation rules are implemented, and these rules are also related to the key type. Such operation rules are more complex and increase the complexity of the encryption process. Finally, the security performance such as comparing improved Arnold scrambling with traditional Arnold algorithm, histogram, key space, correlation, information entropy, differential attack and robustness is analyzed in detail to verify that the proposed algorithm is valid. Compared with the existing advanced algorithms, the experimental results show that the scheme has good performance and improves the security of image encryption and transmission.