Efficient procurement systems are crucial for Nigeria’s public sector development, ensuring transparency, efficiency, cost-effectiveness, ease of control, and monitoring. However, many e-procurement systems face security concerns and lack of trust due to a single individual’s access. This study proposes a decentralized e-procurement system using public key infrastructure (PKI) and multifactor authentication (MFA). Ethereum is used for the blockchain, while public key infrastructure encrypts documents to prevent unauthorized access. MFA uses three factor authentication (3FA) for different users. Simulations show that this combination of techniques reduces fraud between employees and trading partners, demonstrating the potential benefits of a decentralized e-procurement system.