The control of SOx, NOx and CO2 exhaust emission from cruise ships is of particular importance because this type of ship is distinctively “fuel-thirsty” due to its generally very high auxiliary energy requirements, whilst its operational profile is consistent with frequent port calls to urban destinations (i.e. port-cities) which usually posses cultural and/or natural significance. In this thesis a bottom-up methodology based on in-port ships activity has been applied to calculate the exhaust emissions of NOx, SO2 and CO2 produced during the stay (i.e. hoteling) of all the cruise ships at the top 10 cruise terminals within the Mediterranean Sea during 2019. The results indicate that cruise ship traffic produces continuously increasing air pollution in ports over recent years, with top three cruise terminals, in terms of emissions, to be Barcelona, Palma de Mallorca and Venice. More importantly, however, the analysis of the ship emissions reveals that for any given ship traffic involving specific vessels using marine fuel of a given quality, the presence of other factors (e.g. seasonality etc) can also influence the ship emission levels. This is particularly evident in the case of the ports of Mediterranean Sea where Cruises is a common way of vacation, as the weather enhances this type of tourism, and at the same time increases air pollution and costs of associated damage. An additional analysis will be presented, where the results that were found from MRV data base, which is a widely used inventory of entire shipping sector. In subject thesis, it will be used the data from MRV EMSA data base where data is only from European ports. For calculation purposes, it has been chosen passenger shipping only, so as to be compared with the data that have been collected for the subject study.