There are many professions with codes of ethics, the violation of which may be followed by certain sanctions. Examples include lawyers, judges, accountants, doctors and bankers. In the field of business and commerce also, particularly in this age of globalization, a need has long been felt to have codes of business ethics. This concern has led universities to have various courses on this subject and large companies to have codes of ethics applicable to their activities and even international entities to have global pacts on this subject.By the lapse of time, the importance of these codes has increased. So, one can say that, in the near future, companies without a proper code of ethics will lose the market to their competitors in the same way that a company without technical and professional capabilities will do so.Fortunately, rules of ethics have well been reflected in the contents of the Islamic law of commerce, and were used to be observed by merchants in the traditional markets of Iran. In this article, reflection of rules of ethics on the Islamic law of commerce has been discussed by giving various examples and making comparisons to the laws of Iran and certain other countries. The conclusion made is that such teachings should be put into practice by the government, N. G. O.’s, chambers of commerce, trade unions, etc. to make sure that a more ethical approach to commerce and business is adopted and, thus, a more active role is played in the global trade in the age of globalization.