The railway used to be a favorite means of transportation for many citizens, but today it is not in good standing. Despite the many advantages that rail transport has over air, road and other types of transport, if we look at environmental sustainability, safety, economy and comfort, all these advantages fall into the background if the speed of travel and the quality of rail transport decrease. This work describes how liberalization has affected the railway transport market in the Republic of Croatia until now, when through documents, regulations and directives the European union encouraged the liberalization of rail freight transport in the first place. Also, what is the situation regarding rail passenger transport in which HŽPP still holds a monopoly on the market. Even before entering the European Union, the Republic of Croatia begins restructuring and preparing the Croatian railway sector for market liberalization. The Law on Railways, as a fundamental act in the railway sector, is a prerequisite for market liberalization, which begins with the separation of companies that carry out the activity of providing railway passenger and/or cargo services and the activity of railway infrastructure management. This year, Croatia marks ten years since the liberalized rail transport market, and is currently in a period of intensive investment in the rail infrastructure, but under quite a large number of problems.