The book is a collection of best selected research papers presented at International Conference on Network Security and Blockchain Technology (ICNSBT 2025), held at Haldia Institute of Technology, Haldia, West Bengal, India, during January 14-16, 2025. The book discusses recent developments and contemporary research in cryptography, network security, cybersecurity, and blockchain technology. Authors are eminent academicians, scientists, researchers, and scholars in their respective fields from across the world.