Herbert A. Simon was the winner of the Alfred Nobel Memorial Prize in Economics in 1978. He has been the Chairman of both the Board of Dirrectors of the Social Science Research Council and the Behavioral Sciences Division of the National Research Council. As a member of the United States President's Science Advisory Committee, he is not only good at administration, but also very knowledgeable in politics, economics, management, psychology, mathe-matics, and computer science. I had met him and discussed with him during the period of 1981-1982 when I stayed in the United States on an Academic Exchange Program between the National Taiwan Normal University and the University of Missouri-St. Louis. This article is part of my research on Herbert A. Simon's Decision-making Theory and Its Applications in Educational Admi-nistration. The purpose of this research is to discuss Herbert A. Simon's Decision-making Theory and Its Implications in Educational Administration. The method of this research is theoretical analysis approach. This article consists of seven parts. The first part is the introduction of the problem background and studying purposes of this research; the second is to outline the important biography and bibliography of Herbert A. Simon; the third is to analyze the genesis of thought of Herbert A. Simon's Decision-making Theory; the fourth is to present the basic conceptual framework of Herbert A. Simon's Decision-making Thery; the fifth is to point out the logical emperical hypothesis of Herbert A. Simon's Decision-making Theory; the sixth is to make a brief comment on the techniques of Herbert A. Simon's Decision-making Theory; and the seventh is divided into two parts - one is to comment on Herbert A. Simon's Decision-making Theory, the other to analyze the implications in educational administration of his theory. From this research, we can find out some conclusions and point out that Herbert A. Simon's Decision-making Theory carries significant implications in educational administration: 1. To emphasize that decision-making theory is the core function of edu-cational administration. 2. To re-affirm that decision-making theory has an important effect on edu-cational administration organization structure. 3. To establish the rational decision-making concept of educational admi-nistration operation. 4. To emphasize equally on decision-making and executive concepts in edu-cational administration operation processes. 5. To pay attention to the research of dynamic processes and administrative behavior in educational administration. 6. To focus on both individual elements and environmental elements which affect educational administration decision-making process. 7. To stress the importance of communication in educational administration decision-making processes. 8. To develop the concept of organizational equilibrium in edicational ad-ministration decision-making processes. 9. To strengthen the revolution of scientific decision-making techniques of educational administration decision-making. 10. To acknowledge the achievement of organization effectiveness and individual efficiency of educational administration decision-making.