Changes in the structure, phase composition, chemical composition of phases, Vickers microhardness, and contact modulus of elasticity in a high-strength titanium α + β-alloy of the martensitic class VST2 during quenching from heating temperatures in the range 700 - 1000°С have been studied using methods of optical microscopy, x-ray diffraction phase analysis, microindentation, and thermodynamic calculations in ThermoCalc. Good convergence of experimental data and thermodynamic calculations is shown. A relationship has been established between the nature of the change in microhardness and contact modulus of elasticity in the VST2 alloy, quenched from 700... 1000°C, and the evolution of the structure and phase composition of the alloy during quenching.