The subject of research in this thesis is the long-term financing of the company HEP d.d. through issuing of corporate bonds. The research covered all issues of HEP securities, their importance in insuring stability and implementation of planned investment activities, which confirmed that only large and successful companies like HEP can significantly rely on this form of long-term financing. Survive on a market without continuous large investments is a mission impossible. Reconstruction and modernization of existing energy capacities, and initiated accelerated construction of new ones, requires large additional investments. With additional investment, the company insures growth of revenue, and maintains and improves its position on market by investing significant capital in the development and expansion of the company, maintenance and modernization of existing facilities and construction of new production capacities. Professional management of business, maintaining a position on a capital market in period of many years, insurance of liquidity and stability make HEP a strong company. Demand for HEP's Eurobonds confirms that domestic and international institutional investors, banks and insurance companies, recognize HEP as a stable company with good creditworthiness and a strategic investment plan. HEP's goal is to remain among the first in the region that applies advanced technological solutions in the management, production and distribution of energy, and also maintain an important role in Croatian economy.