The present invention refers to a method for locating leakages in non-metallic underground pipes. The purpose of the present invention is to locate leakages in non-metallic pipes transporting fluids that may provoke an environmental impact to occur in underground water and soil, by implanting an electric field of a predetermined frequency into a non-metallic pipe using non-purified water. Water conductivity will be useful for identifying leaking points in an electric field measuring circuit previously installed at intervals of one meter between each other along the pipe section to be tested. The points having the highest intensity of the electric field show the presence of leaking points, thereby avoiding substantial damages to natural resources by early detecting leakages.