Samples of microorganisms from the surface of constructions of Mir Space Station (Mir SS) were taken and examined after 13 years of operation. The following microorganisms were isolated and identified: 12 fungal species belonging to the genera Penicillium , Aspergillus , Cladosporium , and Aureobasidium ; 3 yeast species belonging to the genera Debaryomyces , Candida , and Rhodotorula ; and 4 bacterial species belonging to the genera Bacillus , Myxococcus , and Rhodococcus . The predominant species in all samples was Penicillium chrisogenum . It was shown that the fungi isolated could damage polymers and induce corrosion of aluminummagnesium alloys. We commenced a study of microbial degraders on constructions of the Russian section of the International Space Station (RS ISS). Twenty-six species of fungi, bacteria, yeasts, and actinomycetes, known as active biodegraders, were identified in three sample sets taken at intervals. We founded a collection of microorganisms surviving throughout space flights. This collection can be used to test spacecraft production materials, in order to determine their resistance to biodegradation.