Objective To investigate the changes of serum B2 microglobulin and uric acid levels and their correlation with renal function in patients with type 2 diabetic nephropathy. Methods 55 patients with type 2 diabetic nephropathy treated in our hospital from January 2022 to May 2024 were selected as the observation group. According to the degree of renal function decline, the observation group was divided into normal group (15 cases), mild group (20 cases), moderate group (12 cases) and severe group (8 cases). Meanwhile, 55 healthy subjects who underwent physical examination in our hospital during the same period were selected as the control group. Serum factors [levels of β2-MG, uric acid, serum creatinine, urea nitrogen and cystatin C] in the observation group and the control group were detected and compared. The serum factors of different renal function patients in observation group were compared. The changes of β2-MG and uric acid levels in patients with different renal function and their correlation with renal function were analyzed. Results The levels of serum factor β2-MG, uric acid, CREA, UREA and CysC in observation group were significantly higher than those in control group (P<0.05). The levels of serum factor β2-MG, uric acid, CREA, UREA and CysC in severe group were significantly higher than those in normal group, mild group and moderate group. The serum factors in moderate group were significantly higher than those in normal group and mild group. The serum factors in mild group were significantly higher than those in normal group (P<0.05). The levels of β2-MG and uric acid in normal group were positively correlated with serum CREA (r=0.323, 0.254, P<0.05), UREA (r=0.284, 0.234, P<0.05) and CysC (r=0.309, 0.216, P<0.05) levels; In mild group, β2-MG and uric acid levels were positively correlated with serum CREA (r=0.443, 0.376, P<0.05), UREA (r=0.468, 0.341, P<0.05) and CysC (r=0.417, 0.326, P<0.05) levels. β2-MG and uric acid levels were positively correlated with serum CREA (r=0.598, 0.488, P<0.05), UREA (r=0.546, 0.446, P<0.05) and CysC (r=0.541, 0.411, P<0.05) levels in moderate group. β2-MG and uric acid levels were positively correlated with serum CREA (r=0.761, 0.592, P<0.05), UREA (r=0.697, 0.543, P<0.05) and CysC (r=0.643, 0.512, P<0.05) levels in severe group. Conclusion Serum β2-MG and uric acid levels were significantly increased in patients with type 2 diabetic nephropathy, and were positively correlated with serum CREA, UREA and CysC levels. Serum β2-MG and uric acid levels can be used as important indicators to assess the degree of renal impairment in patients with type 2 diabetic nephropathy.