Radon (Rn-222) and its parent radionuclide Radium (Ra-226) are classified as carcinogen. Human exposes to radon in water via inhalation and ingestion, although ingestion is the only way for radium to enter the human body. In this research, tap water collected from Bornova distinct was studied to determine the concentration of radon (Rn-222) and radium (Ra-226) for evaluating their radiological impact. For this reason, the annual effective doses for ingestion and inhalation were estimated. The measurements were performed using a collector chamber method. The mean concentrations of Rn-222 and Ra-226 were determined as 0.85 and 0.76 Bq/L, respectively. It can be stated that the Rn-222 and Ra-226 concentrations of tap waters here are lower than the international reference levels. Obtained concentration levels were applied to estimate annual effective dose due to the inhalation and ingestion. The dose values are also found to be lower than the recommended maximum values. On the other hand, it should be considered that consumption of these waters (2 L) and average radon and radium concentrations of water are the significant factors for estimating doses.