In slowly deforming intraplate regions, identifying active faults is challenging due to their low slip rates or concealment by recent sedimentation and anthropogenic activity, requiring significant time and resources. We focus on the structural features and spatial extent of a buried active reverse fault, central South Korea. Our approach integrates the structural and paleoseismic records from the fault exposure with 2D and 3D electrical resistivity surveys. In the road construction area, electrical resistivity differentiates the fault’s hanging wall from the footwall in granitic bedrock. The hanging wall yields resistivities of <150 Ω·m, lower than the footwall. Based on these findings, we implemented a 3D survey using five survey lines across a 16 m × 27 m area. The 3D inversion reveals a distinct boundary at 150 Ω·m, delineating a N22°W-direction and asymmetric damage in the fault zone. In the rice cultivation area, 2D surveys were conducted along three survey lines to verify the buried fault. The results revealed a low-resistivity zone (<150 Ω·m) indicating an extensive damage zone. Our findings emphasize the effectiveness of integrating geological observations with 2D and 3D resistivity surveys to increase the precision of fault location and reveal complex internal structures in sediment-covered or urban regions.