At first glance, game theory could support with rational, ideologically neutral arguments the logic necessity of acting ethically in business. Apparently, this is what we learn from the Prisoner’s dilemma, the Peasant’s dilemma or Tit for Tat. All these strategic games suggest that the winning business strategies combine the competitive aggressiveness and the disponibility for cooperation with the other players of the economic game. Consequently, it is only rational to adopt an ethical behavior in business activities, respecting the legitimate rights and interests of different categories of stakeholders. But this view is fallacious, because game theory rather suggests the cooperation between the competitors, which is detrimental to the employees, customers, suppliers etc. On the other hand, excepting utilitarianism, the rest of the major ethical theories deny the moral character of those actions which are motivated by self-interest. This study concludes that game theory cannot offer a solid ground for business ethics.