Induced Draft Fan has a function to suck the gas and ash residual burning on the boiler which will then be removed through the stack. As an important component which always active to operate, often appear interruption or problems arise in ID Fan such as overvibration problem. Overvibration is an engine problem due to unwanted excessive vibrations which can damage the engine components. Therefore, the writer is interested to conduct a vibration study on Induced Draft Fan by processing the output data of measuring instrument which will then conclude whether the vibration problem that happened on the Induced Draft Fan in PLTU Indramayu is in accordance with the provision of ISO or vibration standard of a machine or not. The method used is in the form of data retrieval directly using a vibration measuring device called CSI 2140 Machinery Health Analyzer and through the measurement will form a spectrum that will indicate the problem causing over vibration. The inspection results show that the vibration that occurs in the axial outboard motors in the Indramayu PLTU Fan ID in September 2017 is of 5.09 mm / s, and when compared to the ISO 10816 standards it has entered C zone which means it has worning level machine. In addition, the spectrum formed from the measurement data in September 2017 also shows that there is an indication of bearing damage on the inboard axial motor in ID Fan PLTU Indramayu. Then during the process of running after the replacement of bearings, on December 28, 2017 there was a spike of vibration reaching 8,015 mm / s. After interpreting the figure with vibrational spectrum concluded that there is unbalance so that balancing process can be done that can decrease the vibration up to 4,926 mm / sec.