The topic of the thesis is “Financial analysis of the effects of business expansion of the company HEP-Opskrba d.o.o. into the final consumption market”. The author chose this topic because she is an employee of the company in the energy sector and wants to apply the acquired knowledge to analyse the business of the company. The aim of the analysis was to determine the effects of the company's business expansion on its final consumption market. Business performance assessment is one of the most important parts of the company's analysis because it presents various techniques where the data obtained from financial statements are formed into information which can provide a clear and concrete picture of the actual state of the company. The periods covered are the ones dating from 2010-2013 and from 2014-2017, before and after the introduction of the company into new markets, in order to get a clear overview of the Company's operations. The paper is structured in five chapters. The Introduction, which describes the problems, goals and research methods. In the second chapter, entitled Financial Analysis, basic financial statements and statistic financial indicators are described, while in the next two chapters business profile of the Company and empirical research are included. Based on the above mentioned techniques, the author evaluated the success of the business in the final chapter.