The article is devoted to the research of manifestations of separatism in Southeast Asia. Among the countries of this region, the most pressing problem of separatism is in Thailand, Myanmar, Indonesia and the Philippines. In the process of writing the article, features of the emergence of separatism in each of these countries, its causes, forms of manifestation, centers of distribution and consequences have been considered.The main reason for the emergence of separatist sentiments in all the countries under study was ethno-religious differences in their population. The effect of this factor was strengthened by historical, political, socio-economic factors, sometimes external influences, which together led to the emergence of powerful separatist cells. In Buddhist Thailand, such centers are the Muslim provinces of Pattaya, Yala, Narathiwat and Songhl, whose inhabitants are actively seeking to establish their own state of Pattaya. In the populated mainly Buddhists of Myanmar, the cell of active separatism was formed at its event in the state of Rakhine (Arachan), where, in addition to representatives of the indigenous Burmese subethnic - Arakans who profess Buddhism, the representatives of the most numerous Muslim national minority in the country - Rohingya, who are struggling for independence There are several problems regarding the separatism of the regions in Indonesia. It is the province of Irian Jaya (Western Papua) in the western part of the island of New Guinea, Aceh (Aceh) in the north of the island of Sumatra, East Timor (until 2002, until the proclamation of the independence of East Timor), and settled by the Christians of the South Moluccas. One of the most pressing problems of the predominantly Christian Philippines is separatism and extremism of the Moroccan Islamic people living in the southwestern part of the island of Mindanao and the archipelago Sulu and constantly, but with varying intensity, fights for complete independence or autonomy.Separatism in the countries of Southeast Asia is dangerous because it has active forms of expression and is often accompanied by the activities of Islamic terrorist organizations, so the priority for the countries is the fight against terrorism at all levels.