Graduation thesis presents behavior of steel structures and structural elements under the influance of fire. The main focus in this work was to present all the methodes of fire protection for steel structures that are current in the market and to show all advantages and disadvantages for each fire protection system. In addition fire protection systems for plumbing penetrations are also presented, which have important role in providing sufficient fire resistance of the buildnigs. The thesis also present an example of designing fire protection for the steel column HEB 180 in accordance with European Standard Eurocod 3 – Part 1-2: General rules – Structural fire design [SIST EN 1993-1-2]. In the end of the thesis there is an overview of the standards for structural fire design.