South Sudan, one of the youngest country in the world born as result of civil wars, ethnic conflict between Arabs and Black Africans; religious issue between Islam and Christianity/indigenous belief; problem of not sharing economy particularly in North and South of Sudan, All these complex issues made South Sudan fight till independence; after secession from Sudan government, South Sudan was recognized by United Nations as a country in July 2011; even after getting independence South Sudan is still in civil war, ethnic conflict, sexual violence, and high rate of mortality, causalities, high level of corruption, dispute among South Sudan leaders which lead to mass killing targeting their tribes, the Dinka and the Nuer tribes, and displacement of population within the country and to neighboring countries, famine and humanitarian aid crisis, many opposition forces were formed. This paper analyses critically the case of ethnic conflict and civil war in South Sudan from different lenses; historical background, political system, diversity of tribes and religion, third party intervention during conflicts. Paper also suggests a lesson from Rwanda which led to success of overcoming all issues after genocide against Tutsi in Rwanda; Gacaca court, Rwanda traditional court used to reunite Rwandans, end conflicts among people and reconciliation after genocide against Tutsi of 1994; also negotiation, tolerance, good politicians and fight against corruption among government officers, military forces and civilians can bring hope and better future in South Sudan. The resolution to ethnic conflict, civil war, and diverse issues in South Sudan should be ended by South Sudan government by reconciliation and unity among ethnic groups, and standing as one country, to end corruption, and justice to criminals.