<p>The Internet of Things (IoT) devices are increasingly permeating our daily lives and various industries, but their limited storage capacity poses significant challenges. The InterPlanetary File System (IPFS) is an ideal platform that enables decentralized data storage and sharing, providing content hashes for download and file sharing. However, IPFS lacks robust security mechanisms, making it vulnerable to data tampering, leakage, and unauthorized access. In particular, devices lose control over their data when sharing file hashes with arbitrary devices, enabling unauthorized file sharing without the device’s consent. To address these challenges, we propose a blockchain-based secure and verifiable storage scheme for IPFS-assisted IoT with homomorphic encryption, enhancing security and access control, thereby differentiating it from previous approaches. Specifically, our scheme introduces: (1) an improved Paillier-based homomorphic encryption mechanism that not only ensures data is transmitted on the blockchain in ciphertext rather than plaintext, enhancing privacy protection, but also optimizes computational performance, improving the efficiency of encryption and decryption processes; (2) a novel distributed key management framework that generates random encryption keys to resist brute-force attacks and eliminate single points of failure; (3) a digital signature algorithm for verifying private data, guaranteeing data integrity and authenticity, while preventing unauthorized modifications. Furthermore, our scheme differs from existing solutions by integrating these security enhancements into a unified framework, ensuring stronger protection for IoT data in a decentralized environment. Formal security analysis and performance evaluations confirm the superiority of our method in terms of security, efficiency, and practicality.</p>