The Steam Power Plant (PLTU) plays a crucial role in the national electricity system, making the reliability of the generator, especially the insulation quality of the Stator coil, essential. This study aims to analyze the impact of High Potential (Hipot) testing on the insulation quality of new generator Stator coils by comparing Insulation Resistance, Polarization Index, and Leakage current estimates before and after testing. Insulation Resistance and Polarization Index measurements were conducted twice on each coil, before and after the Hipot Test, to obtain comparative data on insulation conditions. An experimental method was applied to 15 Stator coil samples to acquire comparative data. The results indicate that the Hipot Test does not damage insulation quality; most coils showed increased Insulation Resistance and Polarization Index values after testing compared to before, complying with IEEE Std 43-2013 and indicating healthy insulation conditions. A negative correlation between Insulation Resistance and Leakage current was identified, where higher Insulation Resistance corresponded to lower Leakage current. However, in some samples, increased moisture led to decreased Insulation Resistance and Polarization Index values after testing, indicating insulation degradation. These findings reinforce that the Hipot Test is an effective verification method for initial insulation conditions, but test results should be interpreted considering environmental influences on measurement parameters.