Updated project metadata. Drought is considered as a threat to the sustainability of Mediterranean forests and, of the agro-silvo-pastoral “dehesa” system. Holm oak (Quercus ilex L.) is one of the most representative species of these ecosystems and this abiotic stress causes a high tree mortality rate, being more accused at the seedling stage. In this study, an integrative analysis of transcriptome and proteome in leaves of Q. ilex seedlings under drought conditions was carried out to identify gene products involved in the metabolic pathways related to drought tolerant mechanisms.