Thermoelectrical Pulse Induced Evaporation (TPIE) is a method for synthesizing nanostructures without catalysts in ambient conditions. Various types of carbon nanostructures such as carbon dots, carbon nanotubes, or graphene flakes have been obtained by setting Highly Oriented Pyrolytic Graphite (HOPG) as precursor. On the other hand, graphene as a substrate for electronic devices has been attracted significant interest. However, stability of point defects in graphene, whose presence is known to influence mechanical strength, chemical activation, and magnetoresistance, is rarely studied in strong electric field. In this study, Density Functional Theory (DFT) calculation on two types of self-interstitials (SI’s) in external electric field was performed.