“SIVIM Deciduous Forests” is a thematic database established in 2015, focused on forest vegetation from the Iberian Peninsula and southern France. It was registered in the Global Index of Vegetation Databases (GIVD ID: EU-00-023) in January 2016. All types of temperate and submediterranean non-riparian deciduous forests of the phytosociological classes Carpino-Fagetea sylvaticae, Quercetea pubescentis and Quercetea robori-petraeae (formerly combined in the class Querco-Fagetea) are represented in the database. Currently, it contains 6,642 published vegetation plots of beech, birch, ash, lime and other deciduous mixed forests, as well as forests dominated by different species of deciduous and marcescent oaks, 100% of them classified at association level. Data are stored in TURBOVEG format, and are available upon request from the international vegetation-plot databases EVA and sPlot in semi-restricted regime. The relevés have also been included in SIVIM database, and thus they are freely available online. However, in SIVIM Deciduous Forests geolocation accuracy has been improved and the taxonomy and syntaxonomy unified. Plot size is available for 73% of the relevés, of which 82% are between 100 and 400 m2. Plant taxonomy is standardized to Flora iberica. During the last four years, data of SIVIM Deciduous Forests were requested via EVA and sPlot for different projects, and have been used for several studies with various objectives, from floristic, vegetation and habitat-related topics to macroecological studies, and from local to global scales. Abbreviations: EVA = European Vegetation Archive; GIVD = Global Index of Vegetation-Plot Databases; SIVIM = Iberian and Macaronesian Vegetation Information System.