||This bachelor thesis describes nonprofit sector focusing on the Czech non-governmental organizations (NGOs) and the efficiency of their financing. At the beginning of the thesis I mention key definitions of the nonprofit sector. After that I concentrate on the Czech NGOs, which has moved forward during the last two decades. I describe the history, Czech legislature and types and forms of NGOs. I also measure the influence of NGOs on the Czech economy and make a brief comparison with the foreign non-governmental sector. In the last part I examine the influence of the size of the NGOs (according to revenues) to the efficiency of their financing. In order to analyze this influence, I modify the model KAMF to measure the efficiency of NGOs’ financing. In the empirical part of this work I apply the model on the sample of 109 Czech NGOs and analyze the effect. In order to detect advanced relation between the size of NGO and its efficiency of financing, I have used OLS regression analysis.