Against the backdrop of increasing requirements from the European Union regarding recycling rates - specifically the goal of recycling at least 55% of plastic packaging by 2030 - chemical recycling is becoming increasingly important alongside mechanical recycling. Chemical recycling is particularly suitable for waste rich in polyolefins, i.e., the polymer types polyethylene (PE), polypropylene (PP), and polystyrene (PS). However, there are only a few analytical methods available that can easily, quickly, and, above all, reliably determine the polyolefin content. The subject of this master¿s thesis was to develop and validate a method for determining the polyolefin content in plastic waste through selective dissolution. The method was based on the standard EN ISO 10147, which was significantly adapted and tailored to the waste materials under investigation. The development of the method under optimal experimental conditions (sample-solvent ratio, duration of dissolution, particle size, etc.) was carried out using commercially available reference materials (pure chemicals like PP, PET, PA, etc.) on the one hand, and real waste material on the other. For the latter, real, clean packaging waste was collected, sorted by polymer type using FTIR (Fourier-Transformation Infrared Spectroscopy), and the individual polymer types were processed separately (< 1 mm). In this way, real but homogeneous waste material (including additives, fillers, etc.) was available for each polymer type. The experimental series with reference and real materials demonstrated that the selective dissolution method can reliably determine the polyolefin content of plastic-rich waste. The results suggest that the method offers a promising application in the recycling sector, although further optimizations are necessary to accurately analyze complex plastic mixtures.