The data on the biogenic component fraction of the atmospheric aerosol in Southwestern Siberia have been obtained from ground-based and high-altitude monitoring. It was found that the fraction of total protein does not exceed approximately 10% of the total aerosol mass in the surface layer of the atmosphere. The concentrations of total protein and viable microorganisms in the atmosphere are constant at the altitudes from 500 to 7000 m. So, the fraction of the biogenic component of atmospheric aerosol increases with height. The tentative results on the total protein distribution over different size ranges of atmospheric aerosol particles were obtained with a low-pressure multistage impactor.