This book presents the 8th EAI International Conference on Big Data Innovation for Sustainable Cognitive Computing (BDCC 2025), which aims to explore cutting-edge advancements in big data analytics, cognitive computing, and their role in sustainable development. The conference focuses on AI-driven big data innovations, energy-efficient computing, ethical AI frameworks, and quantum-inspired algorithms. Key themes include smart healthcare, Industry 5.0, digital twins for smart cities, climate resilience, cybersecurity, and green blockchain technologies. BDCC 2025 encourages interdisciplinary collaboration between academia, industry, and policymakers to foster responsible and scalable data-driven solutions. Researchers, practitioners, and engineers are invited to contribute original research, novel applications, and emerging technologies that drive sustainable digital transformation. Topics include federated learning, neuromorphic computing, big data in precision medicine, cognitive IoT, and AI-powered space exploration.