This diploma thesis deals with the evaluation of the economic efficiency of a development project. The theoretical part of the thesis explains the basic concepts in the field of development activities, defines the phases of the project life cycle and the feasibility study. It describes the creation of cash flows, indicators of economic efficiency and possible ways of financing development projects. Furthermore, an analysis of the current economic situation and the impact of the COVID-19 pandemic on development companies is performed in this section. The practical part is devoted to the development project, especially the creation of cash flows and the resulting evaluation of the economic efficiency of the project. This is the construction of three apartment buildings in Pardubice.