Ethics is one of the fundamental theoretical and practical sciences that is used in various sciences and is considered as “objective obligation” in religious teachings. Contrary to the simplistic notion of morality, its definition studies is heeded by Islamic and Western thinkers and is met with various views. While examining and analyzing the maximum and minimum definitions of ethics from the point of view of Islamic thinkers, the present article has put it to the test of comparison with the teachings of the Koran and narrations; and believes that the definition studies of Islamic ethics is based on the worldview and ideology of Islam; and propositions such as “self”, “attributes of virtues and vices”, "power and action”, “disposition”, “non- disposition”, “behavior", “motivation”, “conation”, “free will”, “heaven and hell” play an important role in the reconstruction of the definition studies of Islamic ethics.