Banyuwangi Regency is in thecoastal area of East Java Province. The rapid development of tourism in the Banyuwangi area has increased water demand. Continuous pumping of groundwater is feared to cause seawater intrusion into groundwater in the area. This study aimed to map groundwater vulnerability zones to seawater intrusion and to conserve water resources by analyzing seawater intrusion into the groundwater in the Banyuwangi coastal plain area. The analysis included 6 geo-indicator parameters to assess the influence of seawater on groundwater: increasing chloride concentration, the ratio between Cl and Br, Na/Cl ratio, enrichment of Ca concentration, Simpson’s ratio, and Base Exchange Indices (BEX). 30 samples of groundwater samples were taken to examine the ion major and minor. The groundwater ion test found that 4 samples had chloride values greater than 400 mg/L. A comparison of the Cl/HCO3 ratio shows that the four samples each have a medium and high influence on seawater. The analysis used geo-indicators with 6 parameters: Increased Ca Concentration, Cl/Br Ratio, Na/Cl Ratio, Ca Enrichment, Simpson Ratio, and BEX. The results indicated a medium level of vulnerability to seawater for 4 samples. Validation was carried out using the trilinear piper diagram plotting, and it was proven that the 4 samples were classified as alkaline-chloride groundwater facies, which indicates the presence of seawater intrusion in the area.