OBJECTIVE Several studies have suggested that non-diabetic renal disease (NDRD) was common among non-insulin dependent diabetes mellitus (NIDDM) patients with renal involvement. METHODS The prevalence of NDRD among Chinese NIDDM population in PUMC hospital center was retrospectively studied. Renal biopsy specimens were evaluated with light-, immunofluorescence- and electron-microscopy. The cohort consisted of 33 NIDDM patients who received renal biopsy. RESULTS Patients with both isolated diabetic nephropathy (DN, n = 7) and NDRD (n = 22) had comparable duration of DM, creatinine clearance, serum creatinine, albumin and 24 hours proteinuria, as well as incidences of retinopathy, neuropathy and hypertension. Significantly more patients with NDRD had haematuria (P = 0.030) or non-nephrotic proteinuria (P = 0.016). IgA nephropathy accounted for 40.9% of the NDRD identified. CONCLUSIONS In this study, haematuria and non-nephrotic proteinuria predicted the presence of NDRD among NIDDM patients complicated with renal disease. IgA nephropathy is the most frequent type of NDRD in Chinese.