The question of the role of emotions in morality has always been one of the concerns of moral philosophers from the past to the present. Prinz's theory of moral emotionalism is one of the serious contemporary responses to this issue. This theory is a version of moral sentimentalism. According to this theory, morality is inherently dependent on emotions. In the epistemological sense, moral concepts are not only constructed from emotions but are nothing other than emotions. According to this view of moral emotionalism, moral concepts represent emotions that predispose the moral agent to a specific emotional experience in the range of approval or disapproval. In this article, after the semantics of moral emotionalism, an analysis of the epistemological view of this theory will follow from Prinz's perspective. Then, the evidence he relies on for the sufficiency and necessity of emotions for moral judgment will be examined. Finally, it will be shown that, according to recent findings, Prinz's evidence is not very capable of demonstrating the correctness of his claim.