One of the prohibitions in Law Number 5 of 1999 concerning
the Prohibition of Monopolistic Practices and Unfair Competition is
"cartel." The impact caused by the cartel can not only lead to unfair
competition between business actors. However, it can also cause consumer
losses due to price increases resulting from the cartel of a product or
service. This study aims to analyze the problem regarding the effectiveness
of handling cartel cases by the Business Competition Supervisory
Commission (KPPU) and what factors impede the handling of cartel cases
by the Business Competition Supervisory Commission. This research was
conducted using the Juridical method by reviewing applicable laws and
regulations, and documents such as case decisions. From the results of
studies and interpretations, the handling of the Cartel by the Business
Competition Supervisory Commission is still not effective because several
cases of business actors were finally decided not to have committed
violations. The court annulled several decisions of the Business
Competition Supervisory Commission. In contrast, the factors hindering
the handling of cartel cases are the lack of public awareness to report the
activities of several business actors that lead to cartel indications, the
difficulty of obtaining evidence, and several KPPU decisions being
annulled by the court at the objection level. This research is intended to
produce recommendations to improve the process of handling cases of
violations of monopoly practices and unfair business competition,
especially cartels.