Given growing concerns regarding data security, we develop an enhanced Advanced Encryption Standard (AES) by incorporating chaotic mapping techniques and implement it within a secure data transmission scheme, thereby strengthening protection mechanisms for both data storage and transmission processes. First, we developed a new 2D enhanced hyperchaotic map (2D-EHM) by combining classical 1D chaotic maps and conducted dynamic testing and analysis using bifurcation diagrams, phase diagrams, Lyapunov exponent graphs, and sample entropy. The results demonstrate that the 2D-EHM exhibits stronger chaotic properties compared to existing chaotic maps. Subsequently, we optimized each step of the AES algorithm by incorporating the proposed chaotic map. The enhanced AES achieves higher security at every stage of the encryption process and utilizes two different strong S-Boxes, effectively addressing the issues related to fixed points, reverse fixed points, and short periodic cycles. Based on this, we designed a secure data transmission scheme. Finally, we conducted a security analysis of the data encryption algorithm, and the results confirm the feasibility and effectiveness of our approach.