The invention discloses a distribution transformer grounding structure, which comprises a transformer box wall, and is characterized in that the bottom of a high-voltage side lightning arrester is connected with a first lightning protection grounding wire through an electric wire; a groove is formed in the end, away from the through hole, of the iron core flow guide copper bar, a protruding blockis arranged on the side, close to the iron core flow guide copper bar, of the clamping block, and the first lightning protection grounding wire and the second lightning protection grounding wire sequentially pass through the rope penetrating hole and the groove and then are fixed to the wiring screw. A transition copper bar is clamped between the iron core flow guide copper bar and the transformerbox wall, and a gathering binding post is arranged on the iron core flow guide copper bar. The ends, located in the inner cavity of the transformer box wall, of the high-voltage side grounding columnand the low-voltage side grounding column are each provided with a wiring annular groove. According to the distribution transformer grounding structure, the position and the connection mode of the lightning arrester are reasonably arranged, effective lightning protection is achieved, the grounding column is convenient to install, the internal structure can be detached and replaced independently,the requirement for stable connection after installation and clamping can be met, and the distribution transformer grounding structure is quite worthy of popularization.