Abstract: Jack-up platform "Kantan 2" is taken as the research object, it is studied to develop a fast and accurate approach for performing structural reliability analysis and providing evidence to make decision that the platforms need shutdown and maintenances. An acceleration sensor vibration monitoring system was designed, and on-site testing and the acquisition and process of vibration signal data were conducted for obtaining the structural natural frequencies and modes of the platform. Verification of the accuracy of platform simulation model was carried out through the comparisons of the monitoring and simulation model analysis results. It indicates that the simulation model is acceptably accurate since the results of the monitoring and simulation model calculation are close. Both the reliability analysis approach and the monitoring evaluation techniques of simulation model proposed in the paper are extensively valuable for assessment of jack-up safety.