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Alloys based on vanadium having bcc structure are considered as an alternative to palladium membrane alloys for hydrogen filtering. The membrane alloy (V90Co10) was studied by X-ray photoelectron spectroscopy, scanning electron and confocal microscopy. Gaseous impurities (oxygen, nitrogen, carbon and hydrogen) in the membrane alloy was measured. The surface preparation method for the membrane alloy was developed, this makes possible to reduce roughness (Ra) down to 0.05 μm. It was established that in subsurface layer (∼10 nm) vanadium is in metallic form as well as 4+ and 2+ oxidation levels; while cobalt has only metallic form. Homogeneous distribution of elements in the bulk alloy was proved by chemical microanalysis. The value of hydrogen permeability of the V90Co10 membrane alloy was measured by non-stationary technique within the temperature and pressure ranges (623-723 К and 9-30 kPa, respectively). It was found that the hydrogen permeability of the V90Co10 membrane alloy is comparable with membranes made of metallic palladium. [ABSTRACT FROM AUTHOR]