This paper investigates legislation in the field of building maintenance in the Republic of Croatia, with an emphasis on public buildings. The study aims to provide an overview of relevant laws, technical regulations, and standards pertaining to the maintenance of public buildings and to develop a plan for the maintenance of the building for ten years, using the example of the building of the Faculty of Civil Engineering and Architecture in Osijek. The paper explains in detail the basic maintenance concepts defined by the law, obligations arising from the law, and the importance of maintenance to preserve the basic requirements for the structure during its duration. Relevant laws and technical regulations that must be considered when drawing up the maintenance plan are presented. The maintenance plan and program shall include statutory maintenance activities and other groups of activities necessary to ensure the building's functionality, safety, longevity, and aesthetics. As part of the maintenance plan and program, a financial analysis was made by reducing future costs to present value using the net present value method, and a sensitivity analysis for changes in discount rates. The maintenance plan and program shall make recommendations for reducing maintenance costs and for further improvements in the field of maintenance, including regular monitoring of the condition of buildings and updating maintenance plans to ensure their long-term functionality and conservation. The paper emphasizes the importance of systematic planning and implementation to maintain public buildings.