Indonesia is the world’s largest maritime country, its maritime resources need to be guarded and managed continuously for the welfare and prosperity of the people of Indonesia. One of the examples of issues that attracts attention and is still occurring within the territorial waters of Indonesia is illegal fishing. Indonesia constitutes one of the countries which falls victim to the growing actions of illegal fishing. Illegal fishing constitutes a violation of the law, its impact is not only damaging to the people and state, but also disturbing the stability of security at seas and it also constitutes potential conflicts between Indonesia and other countries. This paper will describe the legal issues pertaining to illegal fishing, how it is regulated from the perspectives of national and international laws, its condition in Indonesia, how illegal fishing cases are handled in Fisheries court as well as what are the efforts made by the Government of RI to overcome and prevent illegal fishing within the territorial waters of Indonesia.