The difference between hemofiltration and hemodialysis mainly includes the principle of action, the adapted disease, and the duration of treatment. 1. Principle of action: (1) The principle of hemofiltration is convection, which generally requires the use of filters with relatively large flux, so the removal rate of small molecules is not high. (2) Hemodialysis, on the other hand, requires dialysis through a filter membrane, and the specific mechanism is diffusion, which is commonly used to remove small molecules, though it is difficult to remove large molecules, which usually belongs to intramembrane exchange. 2. Adaptation to diseases: (1) Hemofiltration: generally commonly used in end-stage renal disease using conventional maintenance hemodialysis can not be controlled by fluid overload, intractable hypertension and heart failure; obvious hyperphosphatemia or severe secondary hyperparathyroidism; uremic neuropathy; cardiovascular function is unstable, multiple organ dysfunction and critical condition of acute kidney injury patients. (2) Hemodialysis: for acute kidney injury such as acute pulmonary edema, unresponsive to diuretics, hyperkalemia, hypercatabolic state, no hypercatabolic state, but no urine for 2 days or oliguria for more than 4 days; end-stage renal disease; acute drug or poison poisoning and other conditions. 3. Duration of treatment: (1) Hemofiltration is generally performed 3 times a week for 4 to 5 hours each time. (2) Hemodialysis generally requires hemodialysis 3 times a week, 4 to 6 hours each time, and 12 to 15 hours of dialysis per week. It is recommended that patients choose the suitable treatment method under the guidance of specialists and standardize the treatment.