The aim of this research was to conduct an investment analysis of compressed natu-ral gas filling station. Compressed natural gas is considered a bridge fuel between petroleum and alternative energy sources due to availability of its sources, its usage period, energy efficiency, safety, ecological characteristics as well as economic via-bility. This research analyses the investment profitability of compressed natural gas for entrepreneurs in Croatia based on an investment analysis in compressed natural gas filling station in the city of Pula. All collected data was analyzed according to the business plan in order to determine the investment value, financial indicators as well as effectiveness indicators. The equipment needed for filling station represents the largest part of the investment since it exceeds 70% of the total investment value. The resulting investment value of the equipment is very similar to the investment analysis in the filling stations of this kind in America and Europe. The analysis of financial da-ta and performance indicators showed that the investment in a filling station of com-pressed natural gas is profitable provided that the minimum quantity sold of com-pressed natural gas in the first year of operations is 850 000 kg. Due to the underde-veloped market of compressed natural gas in Croatia, the biggest challenge is to overcome the problem of small number of vehicles powered by compressed natural gas which prevents it from being profitable without a fleet of vehicles that would de-pend on the filling station. In order to develop the market of compressed natural gas government investments in a fleet of municipal enterprises are required. This would result in a lower fuel and maintenance costs for state enterprises. In addition, it would reduce pollution in the cities, dependence on petroleum products as well as encourage a positive investment cycle for entrepreneurs ultimately from which the citizens would benefit since cheaper motor fuel would be available.