Based on the analysis of traditional maintenance mode, such as breakdown maintenance, preventive maintenance and predictive maintenance, lean maintenance strategy is disscussed according to it. To developed the equipment lean maintenance, a lean maitenance method is provided based on real-time data acquisition. The method benefites from the information integrated frame of manufacturing execution system, by which the real-time data of equipment is got. Based on the real-time data, the principle of status data trigger is discussed in detail, and the dynamic maintenance plan is given on the basis of maintenance rules automatically. Finally, maintenance planning system is developed by the way of system design, including business flow design, function design and principle design.