Indonesia islands are situated in equatorial region with relative high density of thunderbolt rate. As developing country Indonesia builds many generating plants. During lightning stroke, some spikes occurred in turbine-generator vibration monitoring systems. Electromagnetic compatibility (EMC) problem was happened in the systems. This paper proposes mitigation technique to overcome spikes in vibration monitoring systems of a generating plant. The spikes displayed in the monitoring system were evaluated and will be mitigated. A filtering system is one of alternative solutions to cope this problem. Ferrite ring component which is a part of filtering system was recommended to put before load (the monitoring system). The result of Pspice simulation showed that the combination of ferrite ring and shunt capacitor to form L-C LPF can suppress the amplitude of the spikes effectively.