ABSTRACT: In this study, hydrogeochemical and application characteristics of one thermal water, one mineral water and 5cold water samples in Iscehisar (Afyonkarahisar) were investigated. The schists of the Paleozoic Afyon metamorphicsform the basement rock in the study area. Iscehisar marbles are the reservoir rock of the geothermal system. Theimpermeable levels of the Neogene units form the cover rock. Meteoric waters percolate to the reservoir rocks, theyare heated at depth by geothermic gradient and then ascend to the surface as thermal waters and/or ascend to thesurface as cold mineral waters due to heat lost causing longer flow paths. The permeable levels of the Neogene rocksare the aquifer rocks of the cold waters. According to the results of the analysis; the thermal water is Na-Ca-HCO3type, the mineral water is Na-HCO3 type and the cold water samples are Ca-Mg-HCO3 and Ca-Na-HCO3 types. Itis thought that the Mg and Na ions in the cold waters are caused by the metamorphic-volcanic rocks in which theyinteract. According to the silica geothermometers, the reservoir temperatures of thermal and mineral waters varybetween 69-119°C and 46-82°C, respectively. All the ion concentrations except those of As in the cold water samples are compatible with the human consumption limits of ITASHY (2013). The ions concentrations of mineral watersample, except that of Cr, are compatible with the natural mineral water limits of DMSY (2004)