Aim of this work was the development of a new pyrolysis gas chromatographic mass spectrometric method to examine Mediterranean organic natural dyes on materials like sheeps wool, cotton, silk, paper and parchment, which could be performed without difficult sample preparation. This experimental assembly allowed the differentiation of a selection of dyes (madder, cochineal, safflower, saffron, turmeric, weld, Persian berries, indigo, woad, purple, alkanna, brazilwood und campeche wood) of different origin (historic Wiesner collection of the Vienna University of Technology, company Kremer Pigmente and Aristotle University in Thessaloniki). The analytical part was done with gas chromatography/mass spectrometry combined with a pyrolyser, which allowed double shot pyrolysis, so the solid sample could be exposed to both, thermal desorption and pyrolysis. There were analysed with this technique sheeps wool samples dyed with the above mentioned organic natural dyes as well as purple on sheeps wool, cotton, silk, paper and parchment. By the use of selected ion monitoring mode of the mass spectrometer the organic carrier materials were made invisible and thus the low amounts of dyes could be detected without prior removal from their supports.