This article proposes a Substitution box (S-box) in the light of Elliptic Curve Cryptography (ECC) for efficient image encryption. Conventional S-box design is accomplished by various methods having diverse benefits and drawbacks. Nonlinear equations and chaos theory are the most eminent techniques for the S-box design. One of the techniques used for the S-box design and user authentication is the ECC. There are various ECC-based S-boxes in the literature. However, majority of them are designed by adhering to intricate schemes generating a computational burden for multimedia devices. It is observed that a comparative degree of security can be obtained by parameter selection rather than following enigmatic and hybrid cryptographic schemes. In fewer computations, the proposed S-box has achieved an equivalent level of security. When compared to other ECC-based S-boxes, the proposed lightweight S-box exhibits a similar level of nonlinearity as well. Finally, the proposed S-box is used in practice to encrypt images, and the statistical analysis of the encrypted images likewise produces excellent results. A comparison between various S-box encrypted images and the proposed S-box encrypted images has been carried out for further evaluation. Together all these features make the proposed lightweight S-box a much better option in the present resource-constrained Internet of Things (IoT) era. © 2023 IEEE.