In this paper we present some results of the investigation of ice nuclei in the atmospheric aerosol carried out on Lake Baykal in July, 1991. Experimental measurements were performed using filter technique at two stationary points and during a 7-day expedition on board a ship in the southern part of Lake Baykal. Measurement results showed that the concentration of the nuclei in the region under study was close to that measured in other geographical regions (Moldavia and Czechia) and varied from 0.1 to 5 nuclei per liter. Enchanced concentrations of the nuclei were observed only in the regions near centers of industrial activity. We also observed some influence of such meteorological factors as precipitations and wind on the concentration of ice nuclei in the atmosphere. The question on the effect of macroscopic transport of air mass on the concentration of ice nuclei in the region under study requires an additional and more long investigations.