The investigation of microbiological rate of indoor air pollution on Faculty of Building and Environmental Engineering at Białystok University of Technology were made by sedimentation method in accordance with Polish standards (PN-89/Z-04111/01,02,03). Six series of measurements were carried out from autumn 2002 to spring 2003. The results show bad microbiological quality of indoor air on Faculty of Building and Environmental Engineering at Białystok University of Technology. It was found that the number of Staphylococcus, Actinomycetales as well as the total count of bacteria were too high and broke the Polish regulations of the clear air. Because of the students' and other workers' safety, monitoring of microbiological pollution of the indoor air must be done and existing emergency to improve the quality of the air must be lead.