The Meriç Delta is an important wetland in northwestern Turkey where soil properties have been degraded due to environmental changes. Salinity is a serious threat in the Delta region, especially in wetlands and agricultural lands, and this situation negatively affects the ecological balance and agricultural productivity of the region. The aim of this study is to investigate in detail the salinity status of the soils of the Meriç Delta using Geographic Information Systems (GIS) and remote sensing techniques, to map the soil salinity in the region based on the data obtained, and to evaluate the effects of salinity on agricultural activities and the ecosystem in the region. Soil samples were collected from different parts of the delta and analysed in the laboratory for parameters such as electrical conductivity (EC), pH and sodium absorption rate (SAR), and the data obtained were analysed in a GIS environment to produce salinity maps of the delta region. The spatial distribution of salinity levels at different depths was revealed by combining satellite imagery with ground observations. It was found that high salinity levels in the region affect plant root development and limit water use, especially in agricultural production areas. Inadequate irrigation and drainage systems also contribute to the salinity problem. Compared to similar studies in the literature, this study has highlighted the extent of the soil salinity problem in the Meriç Delta and shown that strategic steps should be taken to solve this problem. In particular, it is recommended to improve drainage systems, adopt sustainable irrigation methods and optimise crop cultivation in saline areas. These results are important for the protection of the delta ecosystem and the sustainability of agricultural production.