Diabetic kidney disease (DKD), a common and severe complication of both type 1 and type 2 diabetes, has become the leading cause of chronic kidney disease and end-stage renal disease. Current clinical treatments for DKD mainly focus on glycemic control and renal function protection, but existing strategies still fail to effectively halt the progressive decline of renal function. Patients often eventually progress to renal failure accompanied by cardiovascular complications. The complexity of the pathophysiological mechanisms of DKD determines the limitations of single-target interventions and highlights the necessity of multi-pathway synergistic therapy. Studies have shown that traditional Chinese medicine monomers can exert effects through multiple pathways: they not only regulate disordered glucose and lipid metabolism and alleviate oxidative stress and mitochondrial dysfunction, but also inhibit inflammatory responses, modulate autophagy levels, antagonize apoptosis, and regulate the renin-angiotensin-aldosterone system. This article systematically reviews the recent research progress of traditional Chinese medicine monomers in the intervention of DKD, analyzes the current limitations and deficiencies, and prospects future development directions, so as to provide theoretical support for the research and development of novel therapeutic strategies for DKD.