As a country with humongous-biodiversity, Indonesia has a great deal of natural resources, consisting of plants and animals. According to World Wildlife Fund (WWF) of Indonesia, Indonesia is estimated has about 20% of world’s mammals, 16% of reptiles and amphibians, 17% of birds, 25% of fish, all of them are inhabit the nature of this country. Unfortunately, the magnitude number of those animals are comparable with their extinction threat. This paper is the result of a normative research with statute, analytical and case approaches on protection of endangered animals under Indonesian legal system with special reference to the case of illegal poaching for trade. The study found that there are at least two main underlying causes towards the extinction of endangered animals in Indonesia. First, habitat loss due to the high rate of deforestation; second is illegal poaching for trade. There is linkage between one to another, and both of them contributing to the extinction threat of endangered animals. The Government of Indonesia has to consider the improving of wild animal protection by strengthening the legal system and its enforcement, supervising, controlling and by increasing the function of animal conservation as well. It will become the biggest concern if it relates to evidence of the illegal poaching for trade that has been overcome by Indonesia’s Government.