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Background: Radon as a potential risk of radiation exposure is a natural radioactive element that can emit from rocks and soils. Due to solubility in water, it can be inhaled or consumed by the public. The purpose of this study was carrying out measurement and evaluation of radon concentration in samples of drinking water which are collected from water supplies of Borujerd. Materials and Methods: Dose This research was performed to estimate the annual average effective dose (mSva^-1) to the public from dissolved ²²²Rn of 16 drinking water supplies of Borujerd, western part of Iran. The methodology of the study includes utilizing radon monitoring apparatus, RTM 1688-2, to meter the concentrations of ²²²Rn and ²²⁰Rn dissolved in samples. Results: The measured average of radon concentration was 3.451 Bq.l^-1 which was lower than 11 Bq.l^-1 (the EPA level recommended for drinking water). Total radon annual effective dose, ranged from 5.4×10^-3 to 72.1×10^-3 mSv.a^-1 with an average of 34.9×10^-3 mSv.a^-1 which was insignificant compared to all natural sources, 2.4 mSv. Conclusion: The effective received doses for all age groups were less than the standard limit (0.1 mSv/y) therefore there is no need for treatment of water for removal of ²²²Rn in Borujerd County.