The book "Key Authentication Schemes in Public Key Cryptography" offers a comprehensive examination of key authentication schemes within public key cryptography. In today's digital world, where online payment services are gaining increasing importance, the security of the authenticity of public keys and user signatures is crucial. This specialized book highlights the central aspects of key authentication, which is considered an essential component of public key cryptography. It presents both existing key authentication schemes and their advantages and disadvantages in detail. Additionally, newly developed secure key authentication schemes are introduced, aimed at minimizing the security issues of public key cryptography. The authors, Kumaraswamy Palleboina, V. Janaki, and C.V. Guru Rao, contribute their expertise in this field and provide valuable insights for professionals and students in computer science and information security.