� “Alel” prospect area is administratively located in Lebong District, Bengkulu Province. Object of research in this study are the geochemical characteristics of the geothermal surface manifestations that appear on the surface and alteration of minerals in this area. There are two types of manifestation that occur, those are hot springs and fumaroles. The hot springs that come to the surface have a high temperature with sulfuric water type, water bicarbonate, chloride water, sulfuricchloride water. These manifestations appear due to tectonic activity that works in the area of research. This field is dominated by volcanic rock lithology. There are three types of mineral alteration zonation, argilic zone, transition zone and propylitic zone. This geothermal system is high terrain geothermal system with geotermometer calculation results indicate this field has a high enthalpy geothermal systems with a temperature range of 258ºC to 306ºC. Upflow zone of this field is in the south of the study area. Fluid flows into the North toward the outflow zones are located in the North. Reserves in “Alel” field is based on the calculation of the power density of 214MWe, while the volumetric methods based on a potential of 190 MWe at reservoir temperature of 275ºC with a thickness of reservoir 1607m. The potential of silica scaling is minor because the SSI is 0.85 and the potential corrosion of the pipe is minor because there are no acid mineral. Modeling of this geothermal system is based on fluids geothermometer,gas geothermometer and production well log with the direction.