Saltwater intrusion has become one of the serious threats to freshwater resources in coastal areas, especially in regions with high levels of groundwater exploitation. Palu City, located in Central Sulawesi, Indonesia, is one of the areas facing this issue due to rapid urbanization and significant population growth. The city heavily relies on groundwater, with 2.5 million m3 or 65.63% of its drinking water production sourced from this underground supply. However, the extensive use of groundwater in the area poses a risk of seawater intrusion and degradation. This research aims to analyze the vulnerability of seawater intrusion in the coastal aquifer of Palu Bay using the GALDIT method. The GALDIT method identifies areas highly vulnerable to seawater intrusion and helps in developing targeted management strategies to protect this crucial water resource from natural and human-induced threats. A study of 136 dug wells and boreholes revealed that groundwater use in the area is primarily limited to unconfined aquifers. The vulnerability map generated through the GALDIT method highlights the high vulnerability of West Palu and East Palu Districts, particularly around the mouth of the Palu River, and the Mantikulore District in the eastern part of the research area, where densely populated residential areas are predominant.