The diploma thesis shows the maintenance and reconstruction of the bridge crane that is located in the company Đuro Đaković Thermal Energy Plant in Slavonski Bordo. In first part of thesis, is described in general, who the company ĐĐ TEP it is and what it does, also is described history and the organization and way of working of the company. Besides that maintenance department is explained in detail. Also it's shown the division of the maintenance department and the number of employees. Crane maintenance is a separate maintenance department, and the implementation of activities is described in detail when checking and maintaining cranes. After that the concept, maintenance approaches and strategies is described. The activities for making planned repairs, overhauls and reconstruction. Furthermore, the double-deck bridge crane, its main components, are described. Technical data and the very purpose of the crane in the company. The last chapter shows reconstruction of the crane, boundary buffers, installation of a new PLC cabinet, dismantling control cabins and installation of a new remote control. Cable and sliding lines are write up, moreover it's explained structural solutions for installing them. After the shown reconstruction, described is the checking and maintenance of the drive trolley and narrow winch according to the manufacturer's instructions. The list of tools and special aids for maintenance and testing are displayed. Possible faults are shown brake of the drive motor and possible malfunctions of the narrow winch. Instructions are given for changing the steel one ropes that needed to be changed in order for the crane to receive a license to operate from the state inspectorate. At the end of the work, we conclude that it is extremely important and necessary to keep a track of what has been done by doing inspections and maintenance activities. By regular inspections and maintenance working life of cranes can be extended.