Recently, politics and industry has discussed green hydrogen as one of the carbon-zero energy sources of the future. Besides many other countries, Germany formulates clear goals for the energy transition from fossil to hydrogen energy in its "National Hydrogen Strategy". In order to ensure steady supply of hydrogen and to secure national reserves the underground storage of hydrogen (UHS) is increasingly coming into focus. Germany already has extensive experience in storing natural gas to cover supply shortages in the medium term, which follows same geologic principles as for hydrogen. In general, there are two main underground storage options for hydrogen. While in caverns such as salt-caverns operating UHS localities already exist, hydrogen storage facilities in porous media like aquifers or depleted gas reservoirs are still unrealized. In recent studies such as InSpEE and INSPEE-DS, the Federal Institute for Geoscience and Resources (BGR) provided a sound database of potential salt structures and salt horizons that could be used for UHS. This study gives an overview over the research made within all known types of underground hydrogen storage and discusses each their potential in Germany.