This study was aimed to investigate the sensitivity of natural mycobiota of linen and paper as well as inoculated colonizers Aspergillus jensenii, Cladosporium spaherospermum and Trichoderma harzianum to gamma radiation. These types of molds are frequent colonizers of cultural heritage,which cause it's deterioration. In the experiment we used linen and paper as model materials that containe organic compounds (one of the main component is cellulose, an excellent source of nutrients for molds) and therefore is easily colonized with these microorganisms. The dose of radiation was 7 kGy, and was applied in two different velocities; 0.1 Gy/s and 9.8 Gy/s. Effects were measured by monitoring the growth of mold on 0th, 7th, 14th and 28th day of radiation. The results showed that 7 kGy irreversibly damage Aspergillus jensenii, and Trichoderma harzianum, regardless to dose ratio. When it comes to Cladosporium spaherospermum, it was observed that the mold manages to survive and reproduce if radiated at lower velocity, so it is necessary to apply the dose at higher velocity to achieve a successful decontamination. Natural mycobiota included the species of the genera Alternaria, Cladosporium, Penicillium, Fusarium, Aspergillus, Rhizopus, yeasts and a few others. Among them, the most resistant to radiation were yeasts and species of the genus Cladosporium. There is no consistent conclusion of the fungicidal effectiveness of 7 kGy and dose ratio (0,1 and 9,8 Gy/s) to the members of the natural mycobiota on linen and paper due to the hot-spot contamination phenomena on these materials.