This research is a limestone mapping using geoelectric resistivity method conducted in the Sinampur area of Kutambaru District, Langkat Regency. Basically, the resistivity of various types of rocks that are below the ground surface is measured by injecting currents to the surface of the earth which will then produce resistivity as well as its potential. Meanwhile the Wenner-Schlumberger configuration is used to detect the distribution and depth of limestone in the area. Through the ARES G4 resistivitimeter equipped with 32 electrodes, the output of the potential difference response due to the current being injected into the ground surface is read. The 2-D inversion results (Res2Dinv) show that the Wenner-Schlumberger configuration geoelectric method can be used to determine the spread and depth of limestones and their resistivity values ranging from 500-10000 Ωm. Processing of the data examined using a softwaresurfer 10 will show the contour of each limestone point and its resistivity values ranging from 500-10000 Ωm. sounding and depicting limestone distribution zones at depths of 5 meters, 10 meters, 15 meters, 20 meters, 25 meters and 30 meters.