This paper introduces a method of measuring radioactivity in air aerosol samples with HPGe γ spectrometer. Aerosol particles were collected on a filter by a sampler. Then the filter was compressed to wafer and analyzed by a HPGe γ spectrometer. The radionuclides in the aerosol sample were identified and their concentrations in air were calculated by analyzing the obtained γ spectra. Since the level of radioactivity in aerosol samples was very low

the sample to be measured must be laid on the surface of the HPGe detector

and the coincidence summing effect should be corrected in the analysis.