To obtain high volume fraction low angle grain boundary（LAGBs） and low volume fraction recrystallization microstructure so as to improve the comprehensive properties of aluminum alloy, the effects of High Strain Rate Rolling (HSRR) processing parameters on microstructures and mechanical properties of 7050 aluminum alloy were explored. Electron backscatter diffraction（EBSD），Transmission Electron Microscopy（TEM） were used to characterize the volume fraction of low angle-grain boundarys（LAGBs） and dynamic precipitates. The results show that a high fraction of LAGBs can be obtained by HSRR, and the fraction of LAGBs increases with the increasing strain rate but decreases with the temperature. The fraction of LAGBs is 95.6% with the rolling parameter of 370 ℃/20 s-1. The alloy rolled at 400 ℃/20 s-1 exhibits good comprehensive mechanical properties after 470 ℃/0.5 h short-term solution treatment and 120 ℃/24 h aging treatment, with the ultimate tensile strength of 530 MPa，the yield strength of 442 MPa，the elongation at fracture of 19.1%. The mechanical properties of the plates rolled with the strain rate of 20 s-1 are better than that with the strain rate of 10 s-1 at the same rolling temperature.