One of the most important research works in modern business enterprise is the relation between the purpose of business enterprise and decision making behavior of manager. It is because the coincidence of the former and the latter is considered an ideal type in evaluating the result of business management.  Here I have set up assumptions in order to solve the above statements:  (1) What purpose does the modern business enterprise set up and what kind of economic background does it have?  (2) What is the theory of maximization of stock value among the purposes of business enterprise?  (3) What kind of decision making do we do in the maximization of stock value in busiess administration?  (4) How is the behavior of business financial manager`s intention and decision made?  The result pursued under the above assumptions shows that business manager`s behavior of decision making is affected according to the degree that he gets some information, but basically is determined in consideration of his autonomous stand-point, namely the stability of business enterprise and the stability of manager himself while he faithfully performs his duty which is entrusted by stockholders.  Therefore we come to the conclusion that there is a little gap between a manager`s behavior of decision-making and the purpose of stock value maximization.