The fabrication of tubular microfiltration membranes from PKh18N15 corrosion-resistant steel by the method of radial isostatic pressing and magnetron plasma ion deposition of the surface layer is described. Scanning electron microscopy has been used to study the structure of the substrate and surface layers of the membrane. The flux values of tubular membranes have been found to be 1.39 x 10(-8), 1.88 x 10(-8), and 5.53 x 10(-8) m3/(m(2) Pa s) for the membranes with pore sizes of 1, 5, and 20 mu m, respectively. The possibility of regenerating tubular membranes and restoring their productivity by backwashing has been shown. The service life of the membranes with different pore sizes has been determined during the treatment of make-up water for the sample preparation system of the primary circuit coolant of a pressurized water reactor (WWER).