The difference in the roles of ozone in the troposphere and stratosphere necessitates ozone monitoring in different atmospheric layers. The study presents for the first time a methodology for retrieving vertical ozone distribution from outgoing thermal infrared (IR) radiation spectra measured by the IKFS-2 IR Fourier-spectrometer. The retrieval of the vertical ozone profile is carried out in several steps based on different methods for solving illposed inverse problems. For the final refinement of the vertical ozone distribution, we use a physical-mathematical approach based on the optimal estimation method. We use the RTTOV (Radiative Transfer for TIROS Operational Vertical Sounder) radiative transfer model to solve the direct problem. Closed numerical experiments with IKFS-2 model spectra were conducted to estimate errors and optimize the algorithm. On average, across all latitudes, the error of retrieving total ozone column is 2.3 %, while the error in retrieving tropospheric ozone column is 5.2 DU. We can observe an increase in errors of retrieving vertical ozone distribution elements at high latitudes. Measured IKFS-2 spectra were processed. Based on comparison with ozonesondes, IKFS-2 underestimates ozone content in the troposphere and in the lower stratosphere and overestimates it in the tropopause region (220–80 hPa layer), which is also observed in the IASI (Infrared Atmospheric Sounding Interferometer) measurement data.