Aiming at the security problem of multiple images in transmission, this study proposes a multi-image encryption algorithm based on multi-chaotic systems. First, discrete wavelet transform is adopted to preprocess multiple images to get a large mosaic image. Then, a chaotic sequence is generated using logistic-sine-cosine (LSC) map to generate a matrix O for scrambling pixel positions. Finally, a hyper-chaotic Lorenz system is applied to generate a four-dimensional chaotic sequence. It is used to perform bidirectional diffusion and row-column scrambling on the scrambled image to obtain the final ciphertext image. The proposed method has a simple encryption and decryption process and high execution efficiency. The experimental results have been analyzed from multiple aspects and show that the algorithm has a large key space and can resist multiple attack methods, with good encryption performance and security.