De Materia Medica is an encyclopedic work by Greek physician and botanist Pedanius Dioscorides compiled around the 1st Century A.D. Considered a precursor of modern pharmacopoeia and highly regarded for its accuracy and completeness, the original 5 volume work gathers Egyptian, Middle eastern and Graeco-Roman therapeutic knowledge and is considered a primary historical source about the medicines used in these areas. The present publication is a facsimile of the manuscript known as Dioscurides Neapolitanus (Ms. ex-Vindobonense Greco 1) from the VI-VII century A.D., now conserved in the Naples National Library, that includes the herbarium from Dioscorides’ work. Some 400 different species are presented in 172 illuminated pages, accompanied by commentary and descriptions of each plant. For the first time the facsimile is accompanied by a complete translation of the Greek text. The work is completed by over 200 modern illustrations and extensive commentary compiled by specialists comparing Dioscorides’ with today’s medical and botanical knowledge. In the appendix around 700 diseases considered in the work are presented with their corresponding medicine.