<p>Geomorphodiversity comprehends the diversity of terrain forms which may have scientific, educational, aesthetic, geotouristic and cultural value. Geographic Information Systems (GIS) have an important role in obtaining geomorphodiversity indexes. In UNESCO Global Geopark (UGG) territories, the geomorphodiversity index is a relevant tool to identify and analyze areas with greater diversity of terrain forms, as well as for the preservation and environmental monitoring of geoheritage. The aim of this study was to develop a quantitative index to assess the geomorphodiversity of the Caçapava UNESCO Global Geopark (CUGG) territory. The geomorphodiversity index was obtained from the map algebra derived from the Digital Terrain Model (DTM): (a) slope; (b) drainage density; (c) roughness concentration index; (d) terrain diversity forms. Results were contrasted with land cover and use and with the geosites of the CUGG territory. The highest values of geomorphodiversity occupy 59.76% of the area studied and demonstrate a solid correspondence with the CUGG geoheritage. Over 70% of areas with high geomorphodiversity maintain preserved vegetation covers. Areas with a lower geomorphodiversity values coincide with the flood plain compartments of the territory’s main river channels. Although this result was expected, it cannot be readily anticipated since some flat regions show a higher geomorphodiversity index, influenced mainly by drainage density. The development and implementation of this index represents a significant advancement for geoconservation strategies in the CUGG territory.</p>