The European Structural and Investment Funds are a financial instrument for the implementation of public policies of the European Union, and the Republic of Croatia acquired the possibility of their full use at the time of accession to the European Union, and since then they have been purposefully used in accordance with established national and regional development needs, and in order to fulfil priorities and strategy of the Union as a whole. One of the fundamental priorities of the European Union is to achieve as stronger development as possible, not only of its member countries, but also of the regions within each of them. In accordance with this priority, Croatia adopted the Act on Regional Development whose fundamental purpose is to contribute to the socio-economic development of the Republic of Croatia and create conditions that will enable all parts of the country to strengthen their competitiveness and realize their own development potential. This final thesis focuses on the regional development of the Primorje-Gorski Kotar County. It aims to connect the possibilities provided by the European Structural and investment funds and investigate how their intended use affects the competitiveness of that region. Economic development of Primorje – Gorski Kotar County is determinated by it's natural advantages such as the sea, rugged coastline with a lot of islands and the Gorski Kotar area, rich in forest and wood. Thanks to these natural features, as well as its geographical location, Primorje – Gorski kotar county achieves leading results in labor productivity, especially in the processing industry, which, according to macroeconomic indicators, places it among the leading Croatian counties and represents a distinct competitive advantage for it. Today's economy is characterized by major changes related to technological progress, innovation and digitization, but also a crisis, the immediate consequence of which is a high degree of migration, especially of young, highly educated staff, to countries with a higher living standard. A highly educated workforce, as a driver of transformative economic changes, represents the development potential of this region, which is why achieving the conditions for its survival is extremely important. The technological structure of the County is still dominated by market services with low knowledge intensity (tourism, trade, warehousing, land transport), while knowledge-intensive market services (transportation and highly specialized services) are less represented, which indicates the need for accelerated acceptance and implementation of modern technological solutions and increasing the share of high-tech services (include ICT, telecommunications, research and development). Circumstances related to the corona crisis are certainly an additional incentive for more active acceptance and implementation of technological changes and digitization as a prerequisite for further business. Financial indicators indicate the need for better use of competitive potential in activities that significantly affect the entire economy of the county and ensure its sustainable development. This, in a special way, applies to the processing industry and to the activities of the blue economy (maritime transport, port activities, shipbuilding and overhaul, fishing and aquaculture, coastal tourism, biotechnology and others) and the green economy (energy and waste management, renewable energy sources, green tourism, eco food production and others). Although the Primorje-Gorski Kotar County is one of the oldest counties, whose population has decreased significantly, favorable natural and climatic features are still a strong motive for living and working. The stay of young families, as well as the immigration of new ones, strongly depends on the method of using the potential of resources in the county. Advanced technologies represent the potential for creating jobs with high added value, and therefore it is necessary to start innovative and technologically advanced industries, digitize transport and other infrastructure, connect research laboratories and centers. The development of the University of Rijeka and the fact that the county is characterized by a developed sector of the processing industry represents a great challenge for the synergistic development of these activities, the transformation into Industry 4.0. and further strengthening the competitiveness of products and services based on highly developed technologies. The competitive economic environment with the largest entrepreneurial zone in Croatia, logistics center under construction and numerous brownfield areas represents an exceptional economic basis, that contributes to the development of entrepreneurship. Implementation of projects co-financed from EU funds greatly contributes to the development of all mentioned areas, and the continuous encouragement of their more intensive use certainly represents one of the backbones of the further development of the County. This paper presents the impact of the absorption of European structural and investment funds on the development of the Primorje-Gorski Kotar County. The analysis was carried out on the basis of data available on the official website of the European Structural and Investment Funds on all approved projects in a particular area whose implementation has ended or is still ongoing. The data is divided into Operational Programs (Competitiveness and Cohesion Operational Program and Effective Human Resources Operational Program) and within them into areas of intervention. The Operational Program Competitiveness and Cohesion includes investments in: entrepreneurship, energy, health and social infrastructure, tourism and culture, transport, education, environmental protection and communal infrastructure, while the Operational Program Effective Human Resources includes investments in: high employability and mobility of the workforce, social inclusion, education and lifelong learning and good governance. The goal of the analysis was to determine in which of the mentioned areas is invested the most, and which the least, and how this reflects on its progress and development in terms of growth in gross domestic product and gross added value, economic structure, growth in the foreign trade balance and the creation of new jobs as well as reducing harmful effects on the environment, more intensive inclusion of socially vulnerable groups in the life of society, etc.