121-131Andaman – Sumatra tsunami has caused distress to humanity and natural environment. Damage on the natural system has to be assessed scientifically for sustainable development. Geoelectrical studies are the realistic approach for comparing behavior of aquifer before and after tsunami. A study has been conducted on a shallow aquifer in the coastal region to assess salinity variation due to the impact of tsunami. Significant variations were observed in apparent resistivity values, due to percolation of sea water into shallow aquifers. Transformation of curve types has been noted in few regions in various aquifer depths. Changes in the formation resistivity and formation factor have also been noticed, which indicate salinity increase in aquifers. Geoelectrical cross section of the aquifer shows that perched water lens identified has also been affected by tsunami stress