Since the mass production of plastic started in the 1950’s, the accumulation of plastic litter as well as plastic particles known as microplastics (MP) in aquatic habitats was reported. The primarily examined habitats concerning MP are the marine environment as well as riverine systems and lakes. MP pollution of remote areas like polar regions is currently widely unknown. Until now only one published study proved the abundance of MP in arctic sea ice. This thesis aims to fill this gap of knowledge with an emphasis on MP pollution of sea ice deriving from the Fram Strait, a passage between Greenland and Svalbard. As a first step, an appropriate preparation procedure of ice cores regarding MP analysis was developed. The second step consisted of the identification and quantification of MP via FPA (focal plane array) – based micro – Fourier transformed infrared (FTIR) spectroscopy. In total four ice cores sampled in Fram Strait in 2014 at two different locations were examined. The surface of the ice cores in contact with the driller was removed by scraping and flushing with MilliQ. The cores were cut into pieces, melted, concentrated on Anodisc filters and finally subjected to micro – FTIR spectroscopy. Mean concentrations of 2 x 106 particles m-3 in pack ice and 6 x 105 particles m-3 land-fast ice were detected. Thereby the highest concentration exceeded that of the previously published study on MP in sea ice by 4 orders of magnitude. In total 11 different polymer types were identified, whereas polyethylene (PE) was the most abundant one.