The invention provides a magnetically levitated train rail irregularity monitoring and predicating method, device and system. The monitoring method comprises the steps of obtaining first operation state data and first suspension performance data of a magnetically levitated train operating on practical rails; determining the specific rail irregularity type of rail irregularity points according to first train position information; finding first rail irregularity degree corresponding to the first operation speed and the first suspension performance data from each corresponding relationship of the operation speed and the suspension performance data of each rail irregularity degree of the specific rail irregularity type. By the method, the rail irregularity degree of the rail irregularity points on the magnetically levitated train rail at different time periods can be monitored, so that the monitoring on the magnetically levitated train rail irregularity can be realized; further, the operation safety of the magnetically levitated train can be ensured.