In this book, the author Dr.Ahmad Aghazadeh as a full professor of International and Comparative Education, firstly has been trying to discuss the history of methodological framework of International and Comparative Education in order to better understanding of the nature of this new academic discipline, secondly, his effort has been focused upon a comparative approach to explain some of major present aspects of educational systems in Iran, Germany, Japan, and South Korea in order to clarify the process of these kinds of studies and research works. This book has been organized as a textbook for university students in the field of Educational Science especially in the erea of Comparative Education as well as Primary and Preschool Education at undergraduate, graduate, and postgraduate levels. The author expresses the hope that besides his students, the book will find readers among teachers, education administrators, and those researchers who want to conduct any Comparative studies. As a last word, let us expres our thanks to Dr. Reza Bagherynevisi for organizing framework of the book as a textbook.