Abstract: A collection of about 8000 Expressed Sequence Tags (EST) sequences has been prepared starting from clones belonging to four cDNA peach libraries. Libraries have been prepared from Prunus persica mesocarps at four different developmental stages with the aim to collect data for deep investigation of the maturation process at the molecular level. A fully automated pipeline (ESTree DB) has been prepared to process EST sequences using public software integrated by in-house developed Perl scripts and data have been collected in a MySQL database called ESTree available at this URL: http://www.itb.cnr.it/ESTree. These data are produced in the frame of the activities of the National Consortium for Peach Genomics (ESTree), involving also the Universities of Padova, Udine and other research Institutions.