Tartary buckwheat (TB) has been reported to be associated with a decreased risk of type 2 diabetes mellitus (T2DM), and T2DM has had a major impact on the development of diabetic kidney disease (DKD). Thus, the hypothesis that a daily intake of TB will improve DKD risk factors, including urinary albumin to creatinine ratio (UACR), urea nitrogen (UN), serum creatinine, and uric acid was tested. In a parallel, randomized, open-label controlled trial, 104 T2DM patients were randomly assigned to a diet control group (systematic diet plans and intensive nutritional education) or a TB intervention group (daily replacement of a portion of staple foods with TB foods). Blood samples and dietary information were collected at baseline and the end of the 4-week study. The primary outcomes were that TB significantly decreased the rela tive changes in UACR (2.43–2.35, logarithmic transformed mg/g creatinine) and UN (5.12–4.91 mmol/L) in the TB intervention group vs the diet control group at 4 weeks ( P<0.05), without obvious effect on blood glucose during the 4-week study. In addition, subgroup analyses based on different DKD stages also showed a significant reduction in UACR and UN for the T2DM patients with normoalbuminuria and microalbuminuria ( P<0.05). These results support the hypothesis that TB as a replacement of staple food probably alleviates renal dysfunction in T2DM patients.