Provided is a pharmaceutical composition for preventing or treating diabetic nephropathy, comprising a tensin like C1 domain containing phosphatase (TENC1) inhibitor as an active ingredient. A new target for treating diabetic nephropathy is presented by confirming that TENC1 expression is increased in kidney tissue of diabetes or a podocyte cell line to which a high blood glucose environment is given and experimentally proving that nephrin phosphorylation inhibited by the PTPase activity of TENC1 affects the permeability and mTORC1 signaling of the podocytes resulting in inducing podocyte hypertrophy. As the pharmaceutical composition comprising a TENC1 inhibitor as an active ingredient inhibits nephrin dephosphorylation by TENC1, podocytes damaged from an early stage of the diabetic nephropathy may be protected and the structure and filtration function of the podocytes may be maintained, therefore the pharmaceutical composition is expected to be widely used in preventing or treating the diabetic nephropathy from an early stage.
