This paper proposes an Elliptic Curve Cryptography and Zero-knowledge proof methodology-based secure authentication framework for IoT. Since IoT devices are growing up very rapidly, it is a real challenge to provide strong security while maintaining efficiency. The proposed approach makes use of ECC for lightweight encryption suitable for low-resource devices, while in ZKP, authentication can be perfectly made secure without leaking any private information. It strengthens the features of privacy enhancement and protection against various threats, such as impersonation, replay attacks, and unauthorized access. Extensive security analysis showcases the effectiveness of the framework in terms of attack prevention, and the balance between security and performance is good for real-world IoT applications.