In this paper we report our results on radon exhalation rate of soil as well as indoor radon concentration of a few places of Karbi Anglong District of Assam.The technique of passive method has been adopted using LR-115 (type-II) plastic detector.Significant variations in radon exhalation rate and indoor radon concentration have been observed for the studied locations.The minimum and maximum values of radon exhalation rate as found for the present investigation are 348.37±17.4mBqm -2 h -1 (10.52±0.52 mBqkg -1 h -1 ) and1864.2±92.7 mBqm -2 h -1 (56.29±2.8mBqkg -1 h -1 ).For indoor radon concentration the minimum and maximum values as found from this study are 81.26±4.06Bqm -3 and 277.78±13.89Bqm -3 .