Marine container transportation has shown important developments during recent, years. Due to increased demands for such transportation, the related companies have to enlarge their capacities and establish new lines. The most important criterion to put in a new line is the customer's demand for such a line under marketing conditions. There would be no commercial significance for the supply if the demand is insufficient. The demand can be calculated by the present market, marketing research and cargo statistics between the two ports involved. Marketing research consists of the phases related to identify the targets and the problems, doing the research, developing the plan, collecting and analyzing the data. Another step when establishing a now line is the itinerary of the line and also which ports will be used for the line. Furthermore the present equipment of the ports, technology and possibilities play important role in the selection of the ports. In this research the following aspects have been discussed; the factors which should be considered while the decision is being taken to establish a now container line; analysis of the operation costs, financial analyses and result for the first 5 voyages of the new container fine which was established according to certain assumptions and acceptances.