Abstract: The hot compression deformation of 7075/6009 aluminium composite was studied in the temperature range of 300-500 ℃ and strain rate range of 0.001-1 s-1 by using Gleeble-3500 thermal simulation tester, and the constitutive equation was got. The results show that the flow stress of the composite was significantly affected by strain rate and deformation temperature. The flow stress decreased with the increase of deformation temperature and increased with the increase of strain rate. The peak flow stress behavior of the composite during deformation at high temperature could be described by hyperbolic sine function of Zener-Hollomon parameter. The structural factor A, stress level parameter α and stress index n in the analysis formular of peak flow stress was 1.23×1011 s-1, 0.021 and 6.449, respectively. The hot deformation activation energy of the composite was 168.89 kJ·mol-1.