In this paper, a new spatiotemporal chaos model is proposed. The model is the Hash Arnold Coupled Logistic Map Lattices (HACLML) based on the Arnold Coupled Logistic Map Lattices (ACLML). By introducing hash index chain mapping, the chaotic performance of lattice is improved. Then, a novel image encryption algorithm is obtained based on the HACLML. During the scrambling phase of image encryption, a point-to-block encryption algorithm is designed. In addition, the diffusion encryption algorithm is designed according to the structure of HACLML and double hash index chain. The security analysis results show that the designed encryption algorithm has highly resistant to deciphering.