Objective To explore the clinical values of combined detection of serum cystatin C and serum and urine beta-2 micro- globulin in type 2 diabetic nephropathy. Methods 120 cases of type 2 diabetes nephritis patient were divided into A，B and C group based on urine albumin excretion rate. The serum cystatin C levels were determined by using Olympus AU2700 automatic biochemical analyzer，and the levels of serum and urine beta- 2 Micro- globulin were detected by chemiluminescence immune analyzer. Results The levels of serum cystatin C and serum and urine beta-2 Micro- globulin in each period of type 2 diabetes nephrosis patients were increased significantly ，compared with controls (P < 0. 05). The serum levels of cystatin C in 120 cases of type 2 diabetes nephrosis patient were positively related with the levels of serum and urine beta-2 Micro- globulin ( r=0.428，P < 0. 01 ). Conclusion The combined detection of serum cystatin C and serum and urine beta-2 micro-globulin would have clinical significant in the early diagnosis，prevention and treatment of type 2 diabetic nephropathy.