<p>This paper introduces an enhanced image encryption algorithm that integrates DNA encoding and hyperchaotic permutation to achieve robust security. Unlike existing DNA-chaotic encryption schemes, the proposed method integrates dynamic block-level DNA encoding, XOR-based inter-block diffusion, and probabilistic substitution masks generated from chaotic sequences, enhancing both confusion and diffusion. Initially, the input image is flattened into a vector and permuted using chaotic sequences. A 256-bit key, derived from another chaotic sequence, is then applied via an XOR operation to diffuse the image. The encrypted image is divided into 8 × 8 blocks, each encoded using one of eight DNA encoding schemes determined by a chaotic sequence. To further complicate the encryption, a DNA diffusion process is applied by XORing each block with its predecessor. Additionally, probabilistic substitution is employed using chaotic sequences to govern pixel substitution, ensuring strong resistance against cryptanalytic attacks. Experimental results demonstrate that the proposed algorithm demonstrates high security, robust resistance against common cryptographic attacks, and suitability for secure image transmission applications, with an NPCR of 99.61% and UACI of 33.47%, and an information entropy close to 8.</p>