Aims: In order to assess the long-term influence of high-flux hemodiafiltration (HDF) on hemodynamic stability in patients with dialysis-related amyloidosis. Methods: HDF with high-flux dialyzers was performed for a year in 11 patients who had undergone the surgery for carpal tunnel syndrome. Patients were divided into two groups, and for each group synthetic or cellulose membrane dialyzers were applied. Results: A year after the exchange from standard hemodialysis to HDF with cellulose high-flux dialyzers, β<sub>2</sub>-microglobulin was decreased (45 ± 3 to 28 ± 2 mg/l, n = 5, p < 0.05), but plasma non-refilling ratio was not altered. However, the continuance of synthetic high-flux HDF for a year decreased plasma non-refilling ratio (17 ± 5 to 7 ± 4%, p < 0.05), hypotensive episodes (4.3 ± 0.6 to 2.5 ± 0.4 sessions/month, p < 0.05) and muscle cramps (3.8 ± 0.5 to 1.8 ± 0.5 sessions/month, p < 0.01) in addition to the decrements in serum β<sub>2</sub>-microglobulin (45 ± 5 to 33 ± 2 mg/l, n = 6, p < 0.01). Conclusions: Although the study on a large number of patients may be required to draw a final conclusion, our present data suggest that biocompatible high-flux HDF is uniquely suited for dialysis-related amyloidosis.