The paper analyzes the maintenance of a machining center AXA version VHC 3-XTS, which is used in the enterprise Đuro Đaković Termoenergetska postrojenja Ltd. for processing thick-crag tubular chamber for steam boilers. In the introduction to the generally describes the role and the importance of a maintaining a machining center in modern production. In the example of a machining center AXA is analyzed the implementation of the strategy of preventive maintenance, in order to avoid unplanned downtime machining center. The analysis included the organization of maintenance, preventive cleaning, lubricating and maintenance of certain parts of a machining center at time intervals, way of removing unexpected breakdowns, supply needed's reserve parts, used documentation in the maintenance and use of computer information systems maintenance. It was concluded that the selected maintenance strategy meets the requirements in terms of quality of maintenance of such types of equipment with which to minimize unplanned outages and contributes to maintain the high quality of processing.