The effect of high-temperature annealing (400-1000⁰C) on the development of dislocation rosettes around indents on the (111) plane of GaP crystals has been studied. Features of the development of the shapes of the dislocation rosettes as a function of annealing temperature have been revealed. It has been found that the dislocation structure changes. Experimental data have shown that, at high-temperature annealing of plastic deformation, a linear relationship between the length of dislocation rosette arms and annealing temperature was not observed unlike a low-temperature region. A mechanism for the effect of high-temperature annealing on the change in the shape and size of dislocation rosettes has been proposed. The mechanism is based on the active participation of binary cross slip of dislocations in the heterogeneous stress field under microindentation.