Background: Medical workers are exposed to long-term low levels of ionizing radiation, which makes them vulnerable to DNA damage. There are potential occupational health hazards from radiation exposure in a large occupational segment of the population. Matherials and Methods: During this study, 69 blood samples were taken from 45 medical workers (including diagnostic radiologists, radiographers, and cathlab nurses) and 24 nonmedical workers as controls from three hospitals across Indonesia, and were analyzed for the presence of DNA damage. Detection of γ-H2AX expression as a biomarker of DNA DSB damage and the micronucleus assay were carried out by immunofluorescence microscopy and Giemsa staining, respectively. Results: The mean γ-H2AX foci index in workers was 0.02(0.00-0.24) and in control was 0.02(0.00-0.12), micronucleus frequency of workers (5-30 per 1000 cells) and control (12-29 per 1000 cells). The annual occupational dose of workers was recorded as (0.01-1.12 mSv). There was no statistical difference in the mean number of γ-H2AX foci and the micronuclei frequency between workers and controls, but there was a small tendency toward correlation between γ-H2AX foci and micronuclei frequency and the annual occupational dose of workers. Conclusions: γ-H2AX foci have the potential to be used as a biomarker to detect radiation-induced DNA DSB damage in workers caused by occupational dose exposure.