This thesis examines the inversion of forest heights from single-polarized interferometric SAR measurements of the TanDEM-X mission. For this purpose, the parameterization of the vertical reflectivity function is determined firstly by the model-based Random-Volume-over- Ground (RVoG) approach and secondly by the measurement of a LIDAR (Light Detection and Ranging) waveform. The inversion procedure is implemented for both approaches and va- lidated using the LIDAR datasets for selected sites from the AfriSAR campaign over Gabon. The influence of the imaging geometry or vertical wavenumber and the selected (vertical) vegetation profile on the height inversion results is investigated as well as the influence of multilook techniques to improve the correlation of the two SAR (Synthetic Aperture Radar) images.