One of the most important factors to achieving sustainable development is the need for clean and reliable energy. Renewable energy systems produce clean energy from renewable sources and convert them into energies such as thermal, electric energy and others. The purpose of this study is to select the most appropriate off-grid renewable energy systems for urban and rural areas in South Sudan. Three scenarios are developed based on the potential of the renewable energy resource in each area. The selection of renewable energy systems is done using the Analytic Hierarchy Process (AHP), a mathematical analysis tool used for the assessment of multi-criteria decision-making problems. AHP tackles complex and unstructured decision-making problems involving multiple alternatives by developing a hierarchy for the decision. Super Decisions, a software used for building and assessing decision models, is used for implementing AHP to select the best off-grid renewable energy system for each scenario. A model is developed by structuring the problem into a three-level hierarchy of goal, alternatives and criteria. Criteria weights, local priorities of the alternatives with respect to each criterion and overall priority and ranking of alternatives are calculated and determined. Results show the best alternative for each scenario and the overall most appropriate alternative.