Radon in soil gas had been measured at 39 locations, distributed along three prominent lineaments in the Guwahati city, Assam, India; using solid state nuclear track detectors. The most suitable site is selected from these locations, for continuous radon monitoring by an Alpha-GUARD PQ 2000 on the basis of high average radon concentration, no rock structure in the background and low ground water level even in the rainy season in summer. Influences of ambient temperature, atmospheric air pressure and relative humidity on temporal variation of radon concentration are investigated applying multiple regression method and an equation is derived. Using this equation, radon anomaly peaks are selected and a possible link between these and the observed earthquakes (data collected from USGS and Regional Research Laboratory, Jorhat, Assam, India) have been suggested.