Mg AZ31/Al 7050 laminate was fabricated by co-extrusion directly from the as-cast Mg AZ31 and Al 7050 billets.The influence of annealing temperature and annealing time on microstructure and mechanical behavior of the extruded Mg/Al laminate was systematically studied.Results show that annealing treatments at 250 ℃ for 3 h or at 350 ℃ for 3 h do not result in an obvious grain coarsening of Mg layer and cannot remove the heterogeneous structure.Annealing does not vary texture in the Mg layer,a large fraction of //ND and a small fraction of //TD,but the intensity of component //ND weakens to some extent.Lamellar microstructure in the Al layer remains after annealing at 250 ℃ for 3 h or at 350 ℃ for 3 h.High fractions of the texture components S and cube exist in the extruded sample,and annealing treatment hardly changes their fractions.Post-annealing treatment will largely reduce yield strength of extruded plate and increase plasticity slightly.The yield strength drops from 302 MPa to 206 MPa after annealing at 250 ℃ for 3 h and to 141 MPa after annealing at 350 ℃ for 3 h.The elongation to fracture increases from 1.5％ to 5.4％ after annealing at 250 ℃ for 3 h and to 4.8％ at 350 ℃ for 3 h.The corresponding mechanism was discussed.