FIELD: metallurgy. SUBSTANCE: method of heat treatment of large-size products from high-strength titanium alloy containing wt %: 4.0…6.3 of aluminium, 4.5…5.9 of vanadium, 4.5…5.9 of molybdenum, 2.0…3.6 of chrome, 0…5 of zirconium, 0…6 of stannum, 0…0.5 of silicon, titanium and inevitable impurity - the rest, includes cooling with V1<3°C /min of single-phase β-area up to the temperature T1<370°C and the subsequent aging at the temperature T2=370…600°C during 1…12 hours. After aging the additional heating and processing of alloy in the range T3=T2…Tβ within 1…12 hours, cooling at the speed V2>V1 up to the temperature T4 which isn't higher than T2 temperature, and the subsequent repeated aging in the range of the temperatures T2 within 1…12 hours. EFFECT: increase of strength and impact viscosity.