The measurements of Radon, Thoron and gamma dose was carried out in indoor and outdoor environments at 10 different locations of Bengaluru metropolitan city. It was found that the activity of 222Rn was lower in dwellings of Rajajinagar region and higher in dwellings near Government Science College of Gandhinagar. Interestingly the higher concentration was found in poorly ventilated houses as compared to excellent ventilated houses. The measurement of 222Rn in air and water has yielded a correlation coefficient of 0.83 between themselves. The detailed results are discussed in the present study.