The invention relates to the technical field of commonly used physical resistance reducing materials in the field of power, in particular to a novel high-efficiency anti-corrosive physical resistance reducing agent for a galvanized steel grounding grid. The resistance reducing agent comprises the following components by weight percentage: 38-70% of water-retaining agent, 28-60% of graphite powder, 0.5-2% of graphite fiber powder, and 0.1-2% of inorganic corrosion inhibitor. The resistance reducing agent has good water retention; water content in the resistance reducing agent can be kept; the resistance reducing agent is tightly bonded with surrounding soil; the contact resistance with the surrounding soil is reduced; and corrosion of a grounding material can be alleviated. The conductivity of the resistance reducing agent is further improved by adding conductive paths of conductive matters in the resistance reducing agent; the corrosion of the grounding material is reduced; and the resistance reducing agent is non-toxin, harmless and pollution-free, has a certain corrosion inhibition effect on the grounding material, and is suitable for serving as a physical resistance reducing material for grounding of a power system transmission and transformation station, a power station yard and other large-scale power equipment.