The knowledge of our generations is based on the information and the historical documents that conserve all cultural value for humankind and race, this knowledge was transmitted from ancestral by writing material like parchment, which was made from animal skin. Furthermore, the essential components of parchment were the collagen, water, and inorganic materials. As others nutritive source these writing materials can be the target of many microorganisms especially the fungus. A total of forty historical parchments were collected from different institution, twelve of them were suspected to be infected by microorganisms due to visible color change on the surface of the parchment. The sample collected by sterilized swabs on the different spot of suspected infected parchment, then the specimen cultured on sabouraud dextrose agar (Actidione®) for 7 days at 25 c̊ . The identification is based on the morphology of the colony on the agar and the microscopic observation. As results, after the incubation time at favourable temperature, eight of these twelve historical parchments have an active fungus infection with at least one genus. The detected fungi were respectively six Aspergillus niger, five Aspergillus flavus, three Fycomycetes, one Penicillium funiculosum, and one Trichoderma viride. Finally, the microbial analysis of the infected manuscript which had kept in different national library identified four fungi genus. Further studies are required to identify the species of some fungi using a molecular method, and to study the mechanical effect of this infection on the components of parchment and their elasticity anduse approximately all the method of cleaning for eliminate the effect of fungus reaction on parchment.