Logistics includes an extensive spectrum of operations that are an essential part of the manufacturing enterprise. These operations include purchase, supply chain, manufacture and production, distribution, transportation, inventory and stock, and material flow. Manufacturers strive to improve the effectiveness of these operations, which can be achieved by optimization. As a result of, logistics cost decreases while production efficiency, profit, and business performance increase. The subject of the Diploma Thesis "Logistics system optimization" is an analysis of logistics operations in a selected plant WUSAM, JSC Zvolen. The first, introductory chapters provide a theoretical background of logistics, such as its history and evolution, purchase logistics, supply chain logistics, manufacture logistics, distribution logistics, logistics costs, material flows, and their optimization. These topics are essential for understanding the whole logistics process. The second analytical part deals with the primary aim of this paper: to analyze the plant and its current economic and production status and optimize the logistics operations. For this task were chosen three products from WUSAM, JSC manufacture. All of them were individually analyzed, followed by logistics optimization and economic evaluation of the optimization. Optimization focuses on developing internal transport. This transport will improve goods transport efficiency as well as reduction in costs. Partial optimizations are proposed to improve human resources, pricing policy and production technology. The main contribution of this thesis is that our analysis and subsequent optimization might improve the logistics efficiency and decrease in costs.