The effect of nonstoichiometry and ordering on the lattice constant of the basic lattice of vanadium carbide VC is studied. A change in the lattice constant of disordered carbide VC at the reduction of the carbon content is considered using the direction of static displacements of atoms near a vacancy. A model for the calculation of the basic lattice constant of vanadium carbide is proposed taking into account nonstoichiometry and ordering. It is shown that the ordering of vanadium carbide VC with the formation of V C and V C superstructures results in an increase in the basic lattice constant as compared to disordered carbide.