The microclimate of the nest-sites of Pygoscelis adeliae, P. antarctica and P. papua was studied from December 1979 to January 1981. The temperature of the ground, air temperature at 0.05 m, 0.35 m ad 2 m and wind velocity at 0.35 m and 2 m above the ground were recorded. The wind velocity in the places chosen by penguins for nesting was lower than at the meteorological station by 22% to 60%. It was proved that in winter the mean monthly ground temperature at the nesting places was lower than that at the meterological station by 6 to 8°C due to the much thinner snow cover. Pygoscelid penguins chose for nesting places of specific microclimate and modified the wind velocity, temperature of the ground and, to a leser extent, the air temperature.