Undoubtedly, understanding the theoretical foundations of ethics and its role is essential for achieving ethical guidelines. Cosmological foundations are among the foundations discussed in the field of metaethics, which reflect the views of thinkers on the worlds of existence and the principles governing them. Since the belief or denial of the world of matter and the worlds after the world are influential in the fields of moral epistemology, moral ontology, and moral motivation; This article, written in a descriptive-analytical manner and based on the works and ideas of Feyz Kashani, seeks to explain the foundations of cosmology and its effectiveness in ethics, and has reached achievements such as the meaningfulness of ethics with regard to the belief in the world of the atom, and moral motivation due to the belief in the worlds after this world and the reward and punishment in the hereafter. It has also pointed out the justification of the reason for ethical life due to the belief in the all-seeing controller and the owner of laws and traditions in the world.