What is the moral of the story in The Beautyful Ones Are Not Yet Born?

One moral you might like to consider is the importance of maintaining one's integrity against all the odds. That's what the unnamed protagonist does. Despite the temptations—which include the possibility to enrich himself through bribery and corruption—he remains true to his ideals, refusing to debase himself like so many of his work colleagues. Governments may come and go; but, irrespective of the political situation, people still have to live with themselves. For the protagonist, that means living a life free from the taint of financial and moral corruption.
It isn't easy, of course; our hero has to deal with the contempt of his wife, who resents the fact that he can't provide her and the children with the kind of luxuries that other civil servants are able to procure with their ill-gotten gains. But despite this, the protagonist is able to maintain his dignity throughout the story.
The story lacks of any kind of resolution—or any kind of happy ending—which indicates that this morally upright bureaucrat will never be at rest, and his continued efforts to maintain his integrity will be a struggle, to say the least.

The moral of Ayi Kwei Armah's The Beautyful Ones Are Not Yet Born focuses upon the idea that many fail to be satisfied with their lives as they are. In a search for false security, the man seeks out wealth and power. In this search for wealth and power, the man fails to possess the spiritual clarity necessary for true success. As the man seeks out more wealth and power, he loses his grasp on a morally and spiritually fulfilled life. Therefore, the moral of the novel is twofold.
First, man must come to terms and accept what he has. Success does not always come with great monetary riches and possessions. With one's dissatisfaction with present possessions comes the desire for more. As the man learns, acceptance of having something is better than having nothing.
Secondly, to live a pure and moral life, one must realize that true success comes with the understanding that society does not always positively define who a person is. In some cases, society pushes characteristics upon mankind which actually force a man to turn his back on his internal worth, identity, and strength.