A diagram for the phase equilibria established in the two-component FeVO4-Fe2WO6 system has been constructed from measurements made by DTA and X-ray phase analysis. The diagram shows that the system investigated does not appear as a real two-component system, not even below the solidus line, and that its components form a eutectic mixture with a melting temperature of 810 +/- 5-degrees-C (at a 15.00 mol% content of Fe2WO6).