The article contains provisions on the prevention of sea pollution by ships, including, inter alia, the International Convention for the Prevention of Pollution from Ships, developed in 1973 (MARPOL). The convention aims to protect the marine environment from oil and its derivatives. Special areas, where extraordinary measures have been taken to prevent sea pollution, due to the intensity of ship traffic and the greater threat of damage to the marine environment have also been presented. In the further part of the article, the applicability of various pro-ecological solutions, i.e. the use of catalysts, low-sulphur fuels, and in the case of using residual fuels – exhaust gas scrubbers were described. In the main part of the article, a technical and ecological analysis was made. In addition, difficulties resulting from the use of pro-ecological solutions were described. The costs of using low-sulphur fuel meeting the emission standards, installing the scrubber and modification of the natural gas combustion unit were compared with the assumption of ten years of passenger-car ferry sailing. Then the problems that individual solutions create were shown. In the final part of the article, alternatives to those described, i.e. the liquefied natural gas (LNG) power supply, electric and hydrogen drives were presented.