Abstract. Radon levels were measured in shallow-well water samples collected from Phichit subdistrict in Songkhla province, Thailand. A total of 35 water samples from shallow-wells were collected and measured for the radon concentration. The measurements were performed using a RAD7 portable radon detector. The radon concentrations varied from 0.18 ± 0.07 to 98.1 ± 5.92 Bq/L with a mean value of 16.76 ± 2.33 Bq/L. These recorded values were compared with the safe limit values recommended for drinking water by various health and environmental protection agencies. Thirty-four percent of the recorded values were within the safe limit of 11 Bq/L recommended by the US Environmental Protection Agency. The annual effective dose from ingestion and inhalation of radon was also evaluated. The estimated total effective dose varied from 0.48 to 262.91 µSv/year. The total effective dose in most of the samples (~90%) in this study was within the safe limit (0.1 mSv/year) recommended by the World Health Organization (WHO) and the European Council.