Abstract. The aim of this study was to monitor microbial contamination in the work place of a museum, for estimating the influence of seasons, microclimatic parameters and tourists. The analysis was carried out in artefacts deposits, restoration laboratories and exhibition spaces. The media used to demonstrate the presence of biological agents, nonpathogenic and with pathogenic potential (opportunistic bacteria and filamentous fungi with haemolytic properties) were: simple agar, blood agar and Sabouraud with chloramphenicol. The isolated bacterial strains were identified by API tests and the fungal strains by examination of features with taxonomic value, aspects based on macroscopic observations of colony/cultures and microscopic assessment of mycelia. The counts of the microorganisms in the air were higher especially in the textiles deposits (the mesophilic microorganisms ranged from 200 to 1.4x10 4 CFU/m 3 ). The filamentous fungi most frequently isolated species were: Aspergillus spp.; Penicillium spp., Cladosporium spp. The most frequently isolated bacteria swere: Staphylococcus (S. epidermidis, S. xylosus, S. capitis); Bacillus (B. cereus, Bacillus spp). The results of this study indicate a microbial air load containing both filamentous fungi and bacteria strains, including some opportunistic pathogens which can represent a health risk for the museums workers, especially in the seasons with higher exposure.