The influence of heat treatment techniques on medium temperature creep behaviors of the 4.5%Re single crystal nickel-base superalloy with different heat treatment regimes was investigated by means of creep curve measurement and microstructure observation. Results show that the creep property of the alloy is obviously improved with enhancing the solution temperature due to decreasing the segregation extent of the elements. After fully heat treated, the microstructure of the alloy consists of the cubic g￠ phase embedded coherent in the g matrix. During creep under the condition of 760 °C/800 MPa, no rafted structure of g￠ phase is detected, but the twisted configuration of the g￠ phase is formed in the regions near the fracture. In the ranges of the applied stresses and temperatures, the alloy displays a better creep resistance and a longer creep lifetime. And the deformation features of the alloy during creep are that the dislocations move in the g matrix channels and shear into the g￠ phase, the <110> super-dislocation shearing into the g￠ phase can be cross-slipped from {111} planes to {100} planes to form K-W locking, or the <110> super-dislocation shearing into the g￠ phase is decomposed to form the configuration of (1/3)<112> super-Shockleys partials plus the stacking fault, which may hinder dislocations movement and restrain the cross-slipping of dislocations. This is thought to be the main reason of the alloy having a better creep resistance