Because of the fragility and size of the old master prints and the impossibility to take representative samples, there are no exhaustive studies of the analytical scientific constituent materials. Investigations have been made mainly on the basis of the documentation and conservation. In order to complement these studies with the analytical aspect, the Unidad de Arqueometria (UA) of the Instituto de Ciencia de los Materiales (ICMUV) of the Universitat de Valencia, has developed Energy Dispersive X-Ray Fluorescence (EDXRF) equipment, applied to the art work analysis. This technique provides a global analysis in real time. The EDXRF system is integrated with a X-ray tube and two detectors. The first detector has high energy resolution, and the second one has high efficiency. The use of both detectors allows us to study the presence of a broad range of chemical elements. The data acquisition is made simultaneously with both detectors. In the second part of the paper, we look at some applications of this equipment. First, we present the analysis of the engraving Les hebreux quittent l'Egypte by Johannes Wierix (third plate at the Humanae Salutis Monumenta of Arias Montanus, Anvers: Christophe Plantin, c.1575). Finally, and since the equipment can also analyse flat surfaces of objects, we present the analysis of the Iberian work craft Tesera de Hospitalidad: Caballo de Caminreal.