The estimation of microbiological contamination of air in the diary building was the aim of this survey, especially the influence of level of air contamination as a result of packaging process organization. The total counts of bacteria in the air of production rooms were marked by Koch’s sedimentation method. The total number of bacteria of the most investigation points do not answered to microbial recommended level for air in factory’s HACCP standards. Degree of air contamination depended on work activity and its organization. Increased employees movement and air flow, conducted by washing, transportation and draughts were the most often reason of air contamination increase in the production room.