Diabetic kidney disease (DKD) is the major cause of end-stage kidney disease. However, only renin-angiotensin system inhibitor with multidisciplinary treatments is effective for DKD. In 2019, sodium-glucose cotransporter 2 (SGLT2) inhibitor showed efficacy against DKD in Canagliflozin and Renal Events in Diabetes with Established Nephropathy Clinical Evaluation (CREDENCE) trial, adding a new treatment option. However, the progression of DKD has not been completely controlled. The patients with transient exposure to hyperglycemia develop diabetic complications, including DKD, even after normalization of their blood glucose. Temporary hyperglycemia causes advanced glycation end product (AGE) accumulations and epigenetic changes as metabolic memory. The drugs that improve metabolic memory are awaited, and AGE inhibitors and histone modification inhibitors are the focus of clinical and basic research. In addition, incretin-related drugs showed a renoprotective ability in many clinical trials, and these trials with renal outcome as their primary endpoint are currently ongoing. Hypoxia-inducible factor prolyl hydroxylase inhibitors recently approved for renal anemia may be renoprotective since they improve tubulointerstitial hypoxia. Furthermore, NF-E2-related factor 2 activators improved the glomerular filtration rate of DKD patients in Bardoxolone Methyl Treatment: Renal Function in chronic kidney disease/Type 2 Diabetes (BEAM) trial and Phase II Study of Bardoxolone Methyl in Patients with Chronic Kidney Disease and Type 2 Diabetes (TSUBAKI) trial. Thus, following SGLT2 inhibitor, numerous novel drugs could be utilized in treating DKD. Future studies are expected to provide new insights.