This paper presents an integrate study on the occurrence and distribution of boron in groundwater in the area of Chalkidiki, Northern Greece. Groundwater samples were collected from wells used for drinking and irrigation purposes. Samples were analysed for boron, various physicochemical parameters (T, pH, EC, Ca, Mg, Na, K, Br, Cl, HCO3, SO4, NO3 and As) and isotopes (O-18, H-2, B-11). Boron showed high spatial variation ranged from 0.04 to 6.5 mg/L Almost 60% of the examined wells exhibited boron concentration higher than the limit of 1 mg/L proposed for water intended for human consumption. The higher concentrations were determined in geothermal waters with relatively high temperature. Correlation analysis and hierarchical cluster analysis were employed to find out possible relationships among the examined parameters and groundwater samples. Chemical and isotopic fingerprints have been used to investigate the origin of boron. (C) 2009 Elsevier B.V. All rights reserved.