The aim of diploma thesis is to analyse the capital structure and its optimization in the forest enterprise. This thesis contains two parts: theoretical and practical. The theoretical part is devoted to the optimization of capital structure. The thesis describes the composition of the resources, that is, assets, and also composition of funding sources, it is liabilities. Further, in this section, the theoretical knowledge about the financing of the company's assets is presented. The first part also deals with capital, its costs, its structure and finally the optimal capital structure. The obtained findings serve as the basis for the analysis of the capital structure in the selected forestry enterprise, which includes the practical part of the diploma thesis, which is devoted to detection of the structure of the capital for 5 monitored years in the selected enterprise. In optimizing the capital structure, we based on the theory of the U-curve and the determination of the average capital cost, using the WACC method. The learned findings and the results of the analyses are summarized and evaluated in the Conclusion, where there are also recommendations for setting up an optimal capital structure for an enterprise.