Objective To investigate the clinical manifestations,laboratory findings and renal patho logic changes,as well as their relationships in patients with lupus nephritis (LN).Methods According to the latest classification criteria of lupus nephritis,the clinical manifestations,laboratory findings and renal patho logic changes and their relationships of 281 cases of biopsy proven LN were retrospectively analyzed.Results Totally 281 cases of LN patients were enrolled in total.The ratio of male to female was 1∶9.7.Proteinuria ac companied with hematuria (35.2%) and nephrotie syndrome (33.8%) were the main clinical manifestations. The most common renal pathological change was type Ⅳ LN (35.9%) and type Ⅲ,Ⅳ and Ⅴ accounting for 89.0% totally.The main pathologic changes of nephrotic syndrome were type Ⅳ and Ⅴ,while those who ac companied with renal dysfunction were mainly type Ⅵ and Ⅳ.Most simple hematuria cases showed mild renal injury.However,type Ⅳ and Ⅴ accounted for 40.4% in the 47 cases of LN whose 24 hours urine protein＜ 1.0 g and with normal renal function.Most severe proteinuria was found in Type Ⅴ and higher serum creatinine and anti-dsDNA antibody level were found in type Ⅵ and Ⅳ.The lowest lever of serum complement 3 (C3) was found in type Ⅳ.The amount of 24 hours urine protein showed negative correlation with semm C3 but positive correlation with serum creatinine.Serum C3 demonstrated negative relationship with serum creatinine and anti-dsDNA antibody,while serum creatinine was positively related to anti-dsDNA antibody level. Conclusion The major renal pathological lesions of LN are type Ⅲ,Ⅳ and Ⅴ.There are associations be tween clinical and pathological changes,but axe not always consistent.Proteinuria,low serum C3 and high an ti-dsDNA antibody level may provide clue to severe and active LN.Renal biopsy is important in the diagnosis and progression evaluation of LN.