Statistical analysis: SPSS 13.0.Results: Reduction ratio of ure, creatinin, P, PTH and β2 microglobulin (%) in patients hemodialyzed by LF versus HF dialyzer respectively: 70.24±5.35 vs 69.26±6.55 (p=0.51); 59.94±5.05 vs 60.32±7.41 (p=0.81); 23.84±34.20 vs 24.88±32.86 (p= 0.89); 67.21±23.82 vs 75.78±11.02 (p= 0.03 *); - 22.9±3.9 vs 36.53±25.25 (p<0.001 *).