In the article the variability of concentration of selected chemical proper-ties as well as chemical composition of underground waters intaken by drilled wells on the area of carpathian part of Malopolska province was presented. Men-tioned underground waters occured in the clastic and flysch rocks of Quateriary, Paleogene and Cretaceous period. The chemical properties included the amount of total mineral solids, total hardness and pH reaction of water, whereas chemi-cal composition - the analysis of HCO3-, SO42-, Cl-, NO2-, NO3-, PO43-, Ca2+, Mg2+, Na+, K+, Fe2+, Mn2+ iones concentration. As regards total mineralization the studied waters were described as normal sweet, slightly alkaline and medium hard. Most often they contained higher levels of Fe2+ and Mn2+ iones, sometimes also SO42-, Cl- and Na+. The quantity of statistics variability coefficient of analyzed chemical parameters showed that pH reaction of studied waters was classi-fied as low variable, total mineral solids, total hardness, HCO32-, Ca2+ and Mg2+ (except Quaternary waters), K+ (except Quaternary and Cretaceous waters) as medium variable, Cl-, NO2-, NO3-, PO43- i Mn2+ (only in Quaternary waters), Na+ and K+ (only in Cretaceous waters), Fe2+ and Mn2+ as higly variable (variability coefficient > 100). As regards hydrochemical properties analyzed Quaternary waters were ...