The rapid advancement of quantum computing presents a significant challenge to classical cryptographic systems, threatening the security of widely used encryption protocols. This study explores how quantum algorithms, particularly Shor’s algorithm and Grover’s algorithm, compromise the security of RSA and Elliptic Curve Cryptography (ECC), which rely on the computational difficulty of integer factorization and discrete logarithms. The research underscores the necessity of Post-Quantum Cryptography (PQC) as a proactive response to these emerging threats, focusing on quantum- resistant encryption methods such as lattice-based cryptography, hash-based signatures, and code-based cryptography. Additionally, the study highlights the importance of adopting quantum-safe communication strategies and hybrid cryptographic models to ensure long-term data security. The findings emphasize that industries, governments, and researchers must prioritize transitioning to PQC standards to protect sensitive information from future quantum-enabled attacks. This research provides a roadmap for integrating quantum-resistant cryptographic frameworks and ensuring digital security in the era of quantum computing.