Acute kidney injury (AKI) is a common and serious condition in critical care, making early prediction essential for timely intervention, reduced mortality, and lower healthcare costs. Machine learning methods using electronic health records have shown promise in identifying at-risk patients, but their performance is often limited by reliance on single-institution datasets and poor generalizability across populations. Privacy regulations such as HIPAA and GDPR further restrict cross-hospital data sharing, hindering the development of more robust models.To address these challenges, this study proposes a federated learning–based framework for AKI prediction, enabling multiple hospitals to collaboratively train models without exchanging raw patient data. Each institution acts as a local client that trains on its own data and shares only model updates, which are aggregated into a global model. The framework incorporates standardized feature processing, secure aggregation, and communication-efficient strategies to ensure scalability across heterogeneous healthcare environments.This privacy-preserving approach improves model generalization by leveraging diverse multi-institutional data while maintaining regulatory compliance. Although it introduces challenges such as communication overhead and convergence complexity, these are mitigated through optimized aggregation methods. Overall, the proposed framework enhances predictive performance, supports clinical decision-making, and offers a scalable foundation for future privacy-aware healthcare AI systems in AKI management.