Human development in the environment is altering landscapes, arousing scientific interest in natural resource management, especially in river basins, which are crucial for environmental planning and protection. This study focused on the Itapicuru river basin, in south-west Maranhão, with the aim of analysing its morphometric characteristics, climate and land use. GIS QGIS 3.10.13 was used to determine twelve morphometric parameters based on digital elevation models (scale 1:30,000 from Earth Explorer, SRTM project). Land use was characterised using data from MAPBIOMAS. The drainage area of the basin was 1,201.58 km², with a perimeter of 243 km. Annual rainfall ranged from 1302.58 mm to 1390.31 mm, and the average temperature fluctuated between 26.78 ºC and 27.12 ºC. These data provide an initial basis for managing water resources in the Itapicuru River basin, Maranhão, and for planning integrated management programmes. They are valuable tools for diagnosing and preserving the natural resources of this region, which is constantly changing due to human activity.