Background: This research focuses on study of natural radioactivity (²²⁶Ra ²³⁸U, ²³²Th, ⁴⁰K and ²²²Rn) in different types of water samples at Al-Hurrah City in Najaf province/Iraq using NaI (Tl) and RAD-7 detector. Materials and Methods: Samples have been collected from three major sources of water, City Water (Drinking Water), River Water and Underground Water. The daily consumption of these three sources by humans in construction materials determines the standards used to measure the Radiological Contamination in these sources such as Annual Effective Dose, Radium Equivalent, Absorbed Dose rate, External Hazard Indexes, Internal Hazard Indexes and Activity Concentration Index Due to Gamma Ray of long-live Radioisotopes. Results: The results show that the average of Radioactivity Concentration forRadium-232 were 1.84±0.39Bq/L, 2.31±0.43Bq/Land 7.15±1.88Bq/L, for Thorium-232 were 1.31±0.33Bq/L, 0.98±0.13Bq/Land 2.19±0.44Bq/L, for Potasium-40 were 9.07±1.32Bq/L, 22.29±2.93Bq/Land 40.89±8.93Bq/L and for Radon-222 were 35.5±0.00 mBq/L, 355.50±30.33 mBq/L and 712.00±97.20 mBq/L. Based on Gamma Radionuclides measurement, the mean annual effective doses of city water and river water are lower than the reference level of the effective dose recommended by the ICRP, while the mean annual effective doses of underground water were higher than the reference level of the effective dose recommended by the ICRP.  Conclusion: Finally, the researcher found that all the radiological parameters such as Ra_eq, D, H_ex, H_in and I_γ in the water samples were within the range the global limit, thus it’s safe to use in construction materials.