Groundwater is of the most reliable sources of water for agriculture and drinking. In coastal areas due to saltwater intrusion, determine the interface between fresh and salt water for residents of these areas is very important. In this study, the characteristics of coastal aquifers West and East Babolsar, using geoelectrical studies and geo-electromagnetic studied that these methods are of the most accurate methods in this field. For this purpose 6 sections in the coastline in this area of study were chosen, in each section 15 study locate with 50 meters away in 500 meters coastal distance than with 100, 200, 300, and 400 meters were selected. In order to determining saltwater interface with geo-electric method was assistance of detection wills. With regard to observation data in many points, the results of study showed that the geo-electromagnetic have high accuracy in compere to geo-electric method. Also the results showed that the interface between saltwater and fresh water in the west Babolsar study sections are more than east Bobosar study sections. Over all, with regard to obtained interface depth the saltwater intrusion in each to region exist and it is necessary to tackle of saltwater intrusion in these areas using of management Practices.