The present study aims to locate and rank suitable sites for Soil Aquifer Treatment (SAT) in Jerba Island (South Tunisia) by integrating a single-objective AHP method into a GIS model. The methodology represents a first step in SAT basin construction projects before field investigations. It considers several criteria related to technical, environmental and cost aspects. The result showed that a large area, covering 1489 ha, is suitable for SAT, which exceeds the required area to infiltrate the total treated wastewater produced by all the island wastewater plants. Being situated inside agricultural areas and near coastlines, potential sites for SAT could increase groundwater availability for irrigation and also mitigate existing marine intrusion problem facing Jerba aquifer. The best sites are found closer to Aghir plant than the rest of island WWTPs.