The effects of strain rate on quasi-static and dynamic mechanical properties and fracture behavior of 6005A-T6 aluminum alloy were studied by quasi-static tensile test and dynamic tensile test.The strength of 6005A-T6 aluminum alloy increased with the increase of the strain rate, the tensile strength and yield strength of the strain rate of 200/s increased by 30MPa and 25MPa, respectively, compared with the quasi-static tensile strength. In the process from the quasi-static to the strain rate of 10/s, the tensile strength and yield strength of the material increased most obviously. The plasticity of 6005A-T6 aluminum alloy increases with the increase of strain, but decreases when the strain rate reaches 200/s.Under the condition of high speed tension, the increase of dislocation density and the increase of slip band are the major reasons for the increase of strength and elongation. When the strain rate reaches 200/s, the main reason for the decrease of elongation after fracture is that the grain has no time for large deformation due to the too fast tensile rate.