Paper the most often used substrate in printing, is subjected to many degradation changes. In these processes many alkaline hydrolysis, oxidations or thermoysis participate. The most often reaction is the hydrolytic degradation of the cellulose molecules as the most important constituent species in the paper structure. The mentioned mechanisms interchange in the process of natural ageing. Although the individual values of theses reactions vary, it is supposed that the values of the degradation process are combined with temperature. Because of that it is believed that the results of the accelerated ageing could be useful for creation the conclusion about the mechanism and lawfulness in the conditions of the mentioned phenomena on paper as well as on print. Printing substrates used in investigations are: fine art paper, natural paper and recycled paper. Following printing techniques were used for printing: electrophotography (Indigo E-print 1000, Xerox DC50) and Ink Jet (Epson 1200+) papers and prints were accelerated aged. Further investigations were performed on the new prints accelerated aged and on the prints made on paper which was accelerated aged before. The qualities of the reproduction, mechanical and optical properties of prints were monitored. Color values of 100% of the printed process colors (CMY) decrease also by ageing. The changes are the most visible on Ink Jet and Xerox prints, which is specially stressed on fine art papers. By visual control, by the method of an average observer the obtained results were confirmed by apparatuses. In the scientific sense the investigations are the contribution to the explanation of the optical and mechanical changes and the quality of reproduction in the function of ageing. The investigations are interesting in the application, especially in the quality increase of the determined graphic product.