Abstract: The ethics of ancient Greek mythology and tragedy roughly experienced three stages of development. The first stage is the germination of the concept of blood ethics in mythology. In the myths of the replacement of father and son and the universal infanticide myths, the father and the children follow the law of jungle and succession of the new to the old. The protagonist's inner fear and uneasiness in the process of blood killing and the negative evaluation of violent behavior shows the initial awakening of the consciousness of the kinship ethics. The second stage is the conflict between the concept of blood ethic and the concept of the city. The protagonists of most tragedies, under the impact and challenge of the city-state ethics, choose to hold on to the kinship ethics which is centered on the taboo of incest and killing relatives. The third stage is the deepening and maturity of the ethical concepts represented by the king Oedipus. In Oedipus the King, Oedipus's pursuit of the killer and self-punishment abides by both the kinship ethics and the city-state ethics, achieves an ethical model under the extreme condition of ethical environment.

Key words: Greek mythology, sustaining way of blood, law of jungle, the kinship ethics, the city-state ethics