In view of the microstructure damage and property degradation of directionally solidified DSM11 service turbine blades， it is urgent to study the partial-solution rejuvenation heat treatment. In this study， the effects of different recovery heat treatments on the microstructure and mechanical properties of DSM11 superalloy are studied by using alloys after thermal exposure at 980 ℃ for 500 h with reference to the microstructure of DSM11 blade in real service condition. The results show that bimodal microstructures of 23% secondary γ' phase with the size of approximately 270 nm and 17% coarse degraded γ' phase can be obtained by 1180 ℃/2 h solution combined with 1120 ℃/2 h/AC+850 ℃/24 h/AC recovery heat treatment. Meanwhile， the M ₂₃C₆ carbides at the grain boundary， which are formed during the thermal exposure， are also dissolved. And γ' films on the grain boundary are also partially dissolved. Although the M ₂₃C₆ carbides at the grain boundary can also be dissolved by direct aging at 1120 ℃ without solution heat treatment， the γ' film on the grain boundary changes slightly. The size and volume fraction of the secondary γ' phase are closely related to the solution temperature and the cooling rate after the solution. The secondary γ' phase size obtained by furnace cooling is larger than that obtained by air cooling. The secondary γ' phase obtained at 1160 ℃ solution treatment is completely dissolved in the subsequent aging process and will not be retained in the final. After 1180 ℃/2 h/AC+1120 ℃/2 h/AC+850 ℃/24 h/AC rejuvenation heat treatment， the creep life of degraded DSM11 superalloy is recovered from 18 h to 24 h， which is about 86% of that in standard heat treatment. A certain amount of the reprecipitated secondary γ' phases play an important role in the recovery of mechanical properties.