Heavy metals have potentially detrimental impacts on the whole body or on certain organs. They may induce various sorts of severe disorders, including neuro-, nephro-, carcino-, terato-, and immunological. Humans are exposed to them by breathing, eating, and drinking. Especially, the water sources from which drinking water is derived can represent a route of transmission of heavy metals to the humans. Therefore, waterborne heavy metals even at trace level have become a concern all across the world, including Turkey. The objective of this study was to investigate the elemental concentrations of nine major heavy metals (B, Cr, Ni, Cu, As, Cd, Sb, Hg and Pb) in 125 water samples (25 samples of each of plastic-bottled, glass-bottled, natural mineral, tap and well water) from Istanbul, Turkey using ICP-MS method. Sample preparation and analytical procedure were conducted according to the methods of EPA-3005A and EPA-6020A. Descriptive statistics and associations between the elemental levels in the sampling groups were evaluated by one-way ANOVA using SPSS-19 statistical package programme (P-value<0.05). Our study demonstrated that analyses showed a large range in concentration for most of the elements. Overall, 91.2% of all the waters analyzed fell within the Guideline values recommended by the Ministry of Health in Turkey. However, 8.8% of the samples (7 natural mineral water, 2 tap water, 2 bottled-water and 1 well water) for B, and 0.8% of the samples (1 well water) for Ni were above the safe limits. Based on the order of elemental concentrations, plastic-bottled waters had B > Cu > As > Ni > Pb > Cr > Sb > Cd, glass-bottled waters had B > As > Cu > Ni > Cr > Sb > Pb > Cd, natural mineral waters had B > Cu > As > Ni > Cr > Sb > Hg > Pb > Cd, tap waters had B > Cu > As > Ni > Cr > Pb > Sb > Hg > Cd, and well waters had B > Cu > Ni > As > Cr > Pb > Hg > Sb > Cd. Statistically, there was a positive and significant correlation existing between Ni, Cd, Sb and Pb in the waters, which indicated towards their common source of origin. In conclusion, our study indicated that there was low-to-moderate heavy metal contamination in all the drinking- and well- water samples. There is no a severe health risk for the consumers living in Istanbul because Turkey does not have no other population large enough like Istanbul in which to study high exposures of heavy metals through the waters for human consumption and use.