The present study observed the effect of baicalin on blood glucose and renal function in patients with diabetic nephropathy and explored its mechanism of action. A total of 95 patients diagnosed with diabetic nephropathy by clinical and laboratory examinations were selected and randomly divided into a control and treatment group. The control group included 45 patients who were treated with routine symptomatic treatment. The remaining 50 patients in the treatment group received baicalin, in addition to routine symptomatic treatment. The treatment course was 6 months. Following this, the changes of indicators such as fasting plasma glucose (FPG), glycosylated hemoglobin (HBA1c), aldose reductase (AR) activity, 24-h urinary microalbumin, urinary β2-microglobulin (β2-MG) and urinary albumin excretion rate (UAER) were compared before and after treatment; at the same time, the variations of indexes, including superoxide dismutase (SOD), glutathione peroxidase (GSH-px), nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB), transforming growth factor-β1 (TGF-β1) and vascular endothelial growth factor (VEGF) were detected. Compared with those in the control group, baicalin had little effect on the treatment group's FPG and HBA1c, but it clearly reduced the AR activity and the difference was significant (P<0.05). Baicalin visibly decreased the 24-h urinary microalbumin, urinary β2-MG and UAER (P<0.05) and had notable effect on improving renal function. Following treatment, compared with those in the control group, baicalin distinctly increased the levels of SOD and GSH-px (P<0.05) and decreased the content of NF-κB and VEGF (P<0.05), however, its impact on the expression of TGF-β1 was not statistically significant (P>0.05). The results showed that baicalin may improve the renal function in patients with diabetic nephropathy and delay the progression of diabetic nephropathy through various ways, including anti-inflammation and anti-oxidation.