Catholic moral theology is a major category of doctrine in the Catholic Church, equivalent to a religious ethics. Moral theology encompasses Catholic social teaching, Catholic medical ethics, sexual ethics, and various doctrines on individual moral virtue and moral theory. It can be distinguished as dealing with "how one is to act", in contrast to dogmatic theology which proposes "what one is to believe".

Ethics involves systematizing, defending, and recommending concepts of right and wrong behavior. A central aspect of ethics is "the good life", the life worth living or life that is simply satisfying, which is held by many philosophers to be more important than traditional moral conduct.