_{:The isothermal hot compression test of Cu-1.0%Zr-0.15%Y alloy were carried out by using a Gleeble-1500D thermal simulation machine. The characteristics of true stress-true strain, microstructure evolution and hot deformation mechanism of the alloy were investigated and analyzed at elevated temperature of 550 ℃～900 ℃and at the strain rates of 0.001 s-1～10 s-1. The results show that the typical characteristics of dynamic recovery occurs during the deformation temperature of 550～750℃, while the characteristics of dynamic recrystallization occurs under the deformation temperature of 850～900℃.The deformation temperature and strain rates have significant effects on the microstructure of Cu-1.0%Zr-0.15%Y alloy as hot deformed. Based on the true stress-strain curves, the constitutive equation of the flow stress and strain rates and deformation temperature during isothermal compression deformation is established. The hot deformation activation energy of the alloy is 379.16 kJ/mol, compared with pure copper, the hot deformation activation energy increases by 81% with high Zrcontent. The addition of rare earth element Y not only refines the alloy grains but also promotes the dynamic recrystallization.}