The topic of the thesis is „Financial analysis versus economic analysis in evaluation of cost effectiveness of an investment project“. The paper is divided in two parts and is based on theoretical analysis and the overview of one specific investment project. The theoretical part explains the difference between prefeasibility study and feasibility study, explains the basic methods of evaluation of investment projects, explains in detail making of financial and economic analysis in investment projects using the cost benefit analysis method, defines the risk in investment projects and proposes reduction and elimination of risks. The other part of the thesis is based on a presentation of a feasibility study for the project „Change of use of the site in Vlaška 87 for the needs of an entrepreneurial center”. The applicant for the project is City of Zagreb and the consumer is the Development Agency of City of Zagreb. The City of Zagreb is the owner of the site in question and the feasibility study was made by the author of this thesis and his collaborators. Presentation of the real financial and economic analysis along with the cost benefit analysis will be shown in detail. The role of risks, evaluation of risks and methods of reduction and elimination of risks will be explained at the end of the study. After the mentioned elements, the evaluation of the cost effectiveness of the investment and the justification of the project in question will be given. The project is applying for a public call financed with funds from the European Fund for Regional Development, within the Operational Program “Competitiveness and Cohesion” 2014-2020, within the new Integrated Territorial Investments mechanism and the Strategy of Urban agglomeration Zagreb, specific goal 6.e.2. “Renewal of brownfield locations”. At the end of the paper, a comparative overview of the executed analysis will be given, along with the detailed results of financial and economic analysis of the project in question and advantages and disadvantages of used methods. In conclusion the author will give an evaluation of cost effectiveness of the investment project in question and its impact on the community.