The Ministry of Economy and the Ministry of the Sea, Transport and Infrastructure believes that the upcoming regulations, especially the IMO (International Maritime Organization) Marpol Annex VI on limiting the release of NOX and SOX in ECA (Emission Control Areas) to areas, resulting in the accelerated abandonment of the exclusive use of heavy fuel in ships as they will become impractical and financially penalised. Maritime transport is expected to gradually switch to alternative fuels, with liquefied natural gas LNG in the following text it will be used UPP imposed as a leading energy and therefore plans to create infrastructure and use UPP in the maritime transport of the Republic of Croatia. The UPP sector follows the upward trend of natural gas, most commonly fossil gas today, a fuel that is increasingly recognized as a key energy source for global needs. In last 20 years UPP trade developed rapidly and achieved global growth at a rate of 10 % per year and is expected to continue to grow. In Croatia, such a market still does not exist since the development of UPP infrastructure and markets is a complex and demanding project at the national level. The development of the UPP market should take into account imports of natural gas, local production and possible UPP terminals and the real needs of the markets of Croatia, the region and the European Union. Maritime transport is the one that seems most likely to use UPP both in passenger and in the commercial segment of maritime transport, but it is of key importance to unite all relevant stakeholders in the entire chain from production to import to UPP users. The use of UPP in addition to encouraging the development of new technologies and skills has a positive impact on environmental encumbrance. This paper analyzes the current situation, identified possibilities and implementation of alternative fuels for the implementation of UPP in maritime transport. Primary the possibility of supplying liquefied natural gas from future UPP was considered terminal in the Krk as a unique supply center.