The theory of motivation is a theory which takes the executora’s motivation as the basis of moral judgment. One presupposition of the theory is that motivation can be a common object of understanding. However, motivation exists only in the heart of the executor, and cannot be known exactly by others, so motivation cannot be perceived like a common object, and thus, logically, cannot be the basis of moral judgment. Even if the executor’s motivation is accepted by others and turned into a common object, the motivation still cannot become the valid basis of a moral judgment. This is the dilemma of the theory of motivation. In practice, the dilemma appears as follows: if one insists on the theory of motivation, one can be led to the result that people do evil with good intentions. However, just because motivation cannot be the basis of moral judgment does not mean that motivation is of no significance. Good motivation is always better than evil motivation. Therefore, in moral education we should carry out motivation education and teach people to strive to have good motivations for their behavior. This is the value of motivation theory.