The binary mixture of vanadium with aluminum, cobalt, nickel, zinc, iron, cadmium and molybdenum and the tricomponent mixture of vanadium-iron-nickel can be determined by complex amperometric titration. At pH=10, the complex of vanadium and complex 3 is destroyed with ammonia, and then vanadium is titrated with a 2-3 NH /sub 2/SO/sub 4/ mole salt solution. A single determination of the composition of the binary mixture takes 10-12 minutes, and a single determination of the ternary mixture takes 15-20 minutes.