Objective:To detect urinary polypeptide patterns in stages of the type 2 diabetic nephropathy (DN) in order to screen and find out the potential biomarkers. Methods:A total of 68 urine samples from type 2 diabetic patients with normoalbuminuria(DM1,n = 24),microalbuminuria (DM2,n = 22)and macroalbuminuria (DM3,n = 22),and healthy controls (C,n = 20) were condensed by magnetic beads based weak cation exchange chromatography (MB-WCX),and analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry(MALDI-TOF-MS). ClinProtTM software was used to profile and screen the polypeptide patterns in urine of the patients. Results:When the relative molecular mass < 12 000,there were significant differences in 15 protein peaks between group DM1 and group C(P < 0.01). There was one protein peak of significantly low expression in the group DM2,when compared to group C (P = 0.029 8). And there were significant differences in 10 protein peaks between group DM3 and group C (P < 0.01). Conclusion:MB-WCX coupled to MALDI-TOF-MS is a fast,convenient and high throughput analyzing method capable of screening some relatively specific and potential biomarkers from the urine of DN with different stages.