This book aims to give a brief idea about the basics of nano-chitosan along with its various preparation methods and diversified recent applications in its pure form as well as in the form of nano-conjugates in various fields of biological sciences. This book has been written on this subject matter in order to fulfill the needs of M.Sc students, Research Scholars and Teachers as a reference book of universities. In this book, the subject matter has been presented in a very easy and lucid manner. Most recent information which is appropriate for M. Sc Students, Research Scholars and Teachers have been incorporated in this book from various research papers published in different journals and books available till date. Quite a number of innovative diagrams have been used here to understand the concept more easily. Authors hope that the book in its present form will serve the interest of students, Research Scholars and Teachers effectively.