Monitoring system for oils online was established in the groove of thrust bearing in the ALSTOM units of the Three Gorges Hydropower Station，and a state monitoring system was set up by integrating it with the present realtime monitoring system of the oil film thickness of thrust bearing and the measuring system of the force of thrust bearing.The real time running state of lubricant，oil film thickness of the thrust bearing，force status of the thrust bearing，rated power and speed could be monitored by the system.The system can implement combination of state monitoring information of multiparameter of the thrust bearing，and can provide scientific basis for ensuring safety operation of the hydropower units.