The hot deformation behavior of Al-xMg-2.8Zn alloys at deformation temperature of 300~490 °C, strain rate of 0.001~5 s^-1 was studied by isothermal hot compression tests. After correcting the flow softening from deformation heating in stress-strain curves, Arrhenius-type constitutive equations and processing maps were used to predict and analyze the hot deformation behavior of Al-xMg-2.8Zn alloys. The results show that the flow stress increases with increasing Mg content and strain rate or decreasing temperature. According to the processing maps and corresponding microstructure of alloys, the range of optimum hot deformation parameters of alloys is determined. The range of hot deformation temperature and strain rate both extend and the instability domains extend to the zone of higher temperature and lower strain rate with increasing the Mg content.