As the result of Vietnam Civil war in 1975, many people killed. Most of those who survive from the war tried to flee from the country into other neighboring countries to look for protection and asylum. However, not all of asylum seeker could get what they want. Most of them became refugees and were not accepted by receiving countries due to some reasons. Indonesia as one of neighboring countries of Vietnam also became the destination of Vietnam refugees. Dealing with the problem, UNHCR as the official international organization under United Nations takes a big contribution. However, UNHCR could not play as the only actor. IOM also emerged as another actor that deals with refugees problem in Indonesia although it does not have direct mandate from United Nations in playing its function. Thus, the participation of IOM in dealing with Vietnamese refugees in Indonesia is questioned. This study will provide an analysis of the reason behind UNHCR need another actor to deal with refugee crisis since IOM also has a big contribution and role toward every refugee issue in Indonesia by using role theory and international cooperation concept.