By determining the distribution and extent of geological structures surrounding the Mingyan Tunnel, Xicheng Town, Helong City, Jilin Province, we can evaluate the stability of the rock mass and assess potential hazards during tunnel construction. We use the high-density resistivity method to analyze the subsurface struc-ture of the study area. Conductive anomalies are likely to represent joint and fissure systems within strongly weathered host rocks, and the bedrock surrounding the tunnel is relatively stable and does not contain well-developed faults. High-density resistivity analysis can provide valuable information in the context of tunnel engi-neering and safety.