In this paper we will talk about business ethics, which is a form of applied ethics and about its impact on the business performance. More detailed will be conceptually described moral as an indispensable element of ethics as well of business ethics and relation between these two terms. Here will be considered some elements of business ethics such as ethical norms, the code of ethics, the concept of social responsibility, ways of their implementation and control. The reason for research on this topic is its increasing presence in these days of globalization which has no mercy for anybody. The imperative of business ethics is a concern for all participants in the business process, both internal and external. In order to achieve expected image of the company, they have to build fair and honest relationship with the public. Public opinion makes a selection on the market and is based on public experience about ethical or unethical behaviour of enterprises. This way, business ethics can be the key of competitive advantage and effect on business performance. Theoretical states will be supported by positive and negative examples of true ethical business cases within several Croatian companies. In the first part of the paper focus is on the theoretical explanation of concepts. Later we eil talk about organizational culture, the role of ethics in achieving successful business performance, ethical business practice in the Republic of Croatia and corporate social responsibility.