Hemodialysis is the main treatment of acute and chronic renal failure, and the selection of hemodialysis membrane materials is the key factor that determines the curative possibilities. By changing the membrane forming conditions, we have spun polyvinylidene fluoride (PVDF) hollow fiber membranes with the same inner diameters but different wall thicknesses. Via centrifugal moulding, we have also made membranes into dialyzers to study the mechanical performance of the membranes and the dialysis performance of the dialyzers. The results show that the mechanical performance meets the demand of dialysis. For the dialyzers with 30μm fiber walls, the clearance rates of urea and lysozyme are 90% and 75% respectively, and the rejection rate of bovine serum albumin (BSA) comes to 90% plus. The increase of the mass content of the dope solution polyethylene glycol (PEG) from 19% to 22% decreases the rejection rate of BSA.