Trade association have an irreplaceable role in the growth and development of companies that belongs as its member. Trade association would allow the communication between competing companies and bridges an understanding between companies and the government, thus giving the member of the association to gain an advantage on trade. Even more, trade association can set up rules and recommendation about business practices of its members according to market situations to mitigate losses or to gain more profit. These practices tend to be misused by the trade association to initiate cartel activity in a way that trade association acts as the coordinator of such action and breach Law No.5 of 1999 on the prohibition of monopoly and unfair business practices. By becoming a coordinator of cartel activity trade association would be susceptible to this law and be accountable for its action. Unfortunately, due to trade association not listed directly as the subject of Law No.5 of 1999 trade association position on this law become unclear. As the result, the trade association is often not treated as the subject of this law even if its actions reflected such act. The purpose of this research is to analyze the elements of the subject of Law No.5 of 1999 to see whether trade association would fall under the subject of this Law and also to see the role of the trade association in cartel activities using a normative method with conceptual and statute approach. The result of this research is that trade association are the subject Law No. 5 of 1999 on the prohibition of monopoly and unfair business practices and trade association have a role of coordinator of cartel activity.