Moral decadence has reached an alarming stage in Nigeria to the extent that people now freely engage in all sorts of anti-social behaviours detrimental to national development. Westernization has been conflated with civility and modernity, and African traditional moral values reduced to nothing. The adoption of Western ethical principles as ideals, and the abandonment of African indigenous moral values have done more harm than good to our national development. This paper adopts a critical and conceptual analytic method to address the problem of moral decadence in Nigeria which has eaten deep into the moral fabric of the nation. Indigenous African moral values place emphasis on good character. A good man is a man of good character who refrains from vices and cultivates virtues. African indigenous moral values are preserved in folktales, proverbs, sayings of sages, etiquette and taboos. Individualism is abhorrent to African mentality while family-hood, brotherliness and communalism are the pivot of her moral value system. The fact that Western ethical principles emphasize individualism makes them largely unsuitable for the African mental setting which is mainly communalism. The paper concludes that developing ethical principles from African indigenous moral values and reintegrating them into her value system will go a long way in solving the problem of moral decadence in Nigeria.